Folded telephoto camera lens system

ABSTRACT

A folded telephoto lens system may include multiple lenses with refractive power and a light path folding element. Light entering the camera through lens(es) on a first path is refracted to the folding element, which changes direction of the light on to a second path with lens(es) that refract the light to form an image plane at a photosensor. At least one of the object side and image side surfaces of at least one of the lens elements may be aspheric. Total track length (TTL) of the lens system may be 14.0 mm or less. The lens system may be configured so that the telephoto ration (TTL/f) is less than or equal to 1.0. Materials, radii of curvature, shapes, sizes, spacing, and aspheric coefficients of the optical elements may be selected to achieve quality optical performance and high image resolution in a small form factor camera.

This application claims benefit of priority of U.S. ProvisionalApplication Ser. No. 61/949,861 entitled “FOLDED TELEPHOTO LENS SYSTEMS”filed Mar. 7, 2014, the content of which is incorporated by referenceherein in its entirety.

BACKGROUND

1. Technical Field

This disclosure relates generally to camera systems, and morespecifically to lens systems for small form factor cameras.

2. Description of the Related Art

The advent of small, mobile multipurpose devices such as smartphones andtablet or pad devices has resulted in a need for high-resolution, smallform factor cameras for integration in the devices. However, due tolimitations of conventional camera technology, conventional smallcameras used in such devices tend to capture images at lower resolutionsand/or with lower image quality than can be achieved with larger, higherquality cameras. Achieving higher resolution with small package sizecameras generally requires use of a photosensor with small pixel sizeand a good, compact imaging lens system. Advances in technology haveachieved reduction of the pixel size in photosensors. However, asphotosensors become more compact and powerful, demand for compactimaging lens system with improved imaging quality performance hasincreased.

SUMMARY OF EMBODIMENTS

Embodiments of the present disclosure may provide a high-resolutiontelephoto camera in a small package size. A camera is described thatincludes a photosensor and a compact folded telephoto lens system. Inembodiments, folding the optical path of the camera lens system mayfacilitate achieving a small form factor for the camera lens assembly,and may also facilitate achieving a high resolution optical lens systemusing a relatively small number of lens elements in the small formfactor. Embodiments of folded telephoto lens system are described thatmay provide a larger image and with longer effective focal length thanhas been realized in conventional small form factor cameras. Embodimentsof a telephoto camera including the folded telephoto lens system may beimplemented in a small package size while still capturing sharp,high-resolution images, making embodiments of the camera suitable foruse in small and/or mobile multipurpose devices such as cell phones,smartphones, pad or tablet computing devices, laptop, netbook, notebook,subnotebook, and ultrabook computers. In some embodiments, a telephotocamera as described herein may be included in a device along with awider-field small format camera, which would for example allow the userto select between the different camera formats (telephoto or wide-field)when capturing images with the device.

Embodiments of a folded telephoto lens system are described that mayinclude four lens elements with refractive power. However, more or fewerlens elements may be used in some embodiments. In various embodiments, alight path folding element such as a plane mirror or a prism element maybe used to fold the light optical path by redirecting or reflecting thelight from a first optical axis on to a second optical axis. In at leastsome embodiments, at least one of the object side and image sidesurfaces of at least one of the lens elements is aspheric.

In at least some embodiments, the folded telephoto lens system includesa folded optical axis (referred to herein as AX) that includes a first(object side) optical axis and a second (image side) optical axis, afirst group (referred to herein as GR1) of refractive elements, a lightpath folding element (e.g., a prism or plane mirror) that folds thelight optical path by redirecting or reflecting the light from the firstoptical axis on to the second optical axis, a second group (referred toherein as GR2) of refractive elements, and a photosensor at the imageplane. At least some embodiments may also include an infrared filter. Atleast some embodiments of a folded telephoto lens system may includezooming capabilities for focusing an object scene at infinity (objectdistance from camera ≧20 meters) to near object distance (<1 meter). Forexample, in various embodiments, the first group (GR1), the second groupGR2, and/or the photosensor at the image plane may be zoomed, moved ortranslated for focusing an object scene from far distance (≧20 meters)to near distance (<1 meter).

In at least some embodiments, the lens system may be a fixed foldedtelephoto lens system configured such that the absolute value of theeffective focal length f of the lens system is at or about 14millimeters (mm) (e.g., within a range of 8 mm to about 14 mm), theF-number (focal ratio) is within a range from about 2.4 to about 10, thefield of view (FOV) is at or about 26 degrees, and the total tracklength (TTL) of the unfolded lens system is within a range of 8 mm to 14mm. The total track length (TTL) of a telephoto lens system is thedistance on the optical axis (AX) between the front vertex at the objectside surface of the first (object side) lens element and the imageplane. In embodiments of the folded telephoto lens system, the unfoldedtotal track length (TTL) of the lens system may be defined as thedistance on the folded optical axis (AX) between the front vertex at theobject side surface of the first (object side) lens element and theimage plane. In other words, the TTL for the folded telephoto lenssystem is the sum of the absolute values of the distances on the foldedaxis, AX, between the front vertex at the object side surface of thefirst (object side) lens element and the reflecting surface of lightpath folding element (mirror or prism) and the absolute value of thedistance between the reflecting surface and the image plane. The sum ofthe absolute values of the distances may be used here since by opticaldesign convention, the algebraic signs of the optical parameters (suchas radii of curvatures, distances, focal length, etc.) change signsfollowing a reflecting surface. More generally, the lens system may beconfigured such that the telephoto absolute value ratio (TTL/f) of thefolded lens system satisfies the relation,

0.8<TTL/f≦1.0,

where f is the absolute value of the effective focal length. To beclassified as a telephoto lens system, TTL/f is less than or equal to 1.Thus, embodiments may provide telephoto lens systems. However, note thatin some embodiments a folded lens system may be configured or may beadjustable so that the telephoto ratio is greater than one (TTL/f>1.0),and thus embodiments may encompass non-telephoto folded lens systemsand/or folded lens systems that are adjustable between the telephotorange and the non-telephoto range.

In at least some embodiments, the folded telephoto lens system may beconfigured such that the effective focal length f of the lens system is14 mm, and the F-number is 2.8. However, note that the focal length(and/or other parameters) may be scaled or adjusted to meetspecifications of optical, imaging, and/or packaging constraints forother camera system applications, for example for larger form factorcamera applications. In addition, in some embodiments, the foldedtelephoto lens system may be adjustable. For example, in someembodiments, the folded telephoto lens system may include an adjustableiris or aperture stop. Using an adjustable aperture stop, the F-number(focal ratio, or f/#) may be dynamically varied within a range of 2.8 to10 or higher. Moreover, in some embodiments, the folded lens system mayalso include a zooming mechanism for dynamically focusing an objectscene from far distance at infinity (i.e., ≧20 meters) to near objectdistance (i.e., <1 meter).

The refractive lens elements in the various embodiments may be composedof plastic materials. In at least some embodiments, the refractive lenselements may be composed of injection molded optical plastic materials.The fold mirror and prism elements in the various embodiments may becomposed of glass or plastic materials. However, other suitabletransparent optical materials may be used. Also note that, in a givenembodiment, different ones of the lens elements may be composed ofmaterials with different optical characteristics, for example differentAbbe numbers and/or different refractive indices. Also note that, whilethe lens elements in the various embodiments are generally illustratedas being circular lenses, in some embodiments one or more of the lensesmay be of other shapes, for example oval, rectangular, square, orrectangular with rounded corners.

In at least some embodiments of the folded telephoto lens system, thelens element materials may be selected and the refractive powerdistribution of the lens elements may be calculated to satisfy a lenssystem focal length requirement and to correct the chromatic aberrationsand the field curvature or Petzval sum. The monochromatic and chromaticvariations of the optical aberrations may be reduced by adjusting theradii of curvature and aspheric coefficients or geometric shapes of thelens elements and axial separations to produce well-corrected andbalanced minimal residual aberrations, as well as to reduce the totaltrack length (TTL) and to achieve image quality optical performance andhigh resolution in a small form factor lens system camera.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B are cross-sectional illustrations of an exampleembodiment of a compact telephoto camera including a folded telephotolens system that includes four refractive lens elements and a foldmirror that acts to fold the optical path.

FIG. 2 illustrates a plot of the polychromatic ray aberration curvesover the half field of view and over the visible spectral band ranging470 nm to 650 nm for a folded telephoto lens system as illustrated inFIGS. 1A and 1B.

FIGS. 3A and 3B are cross-sectional illustrations of another exampleembodiment of a compact telephoto camera including a folded telephotolens system that includes four refractive lens elements and a foldmirror that acts to fold the optical path.

FIGS. 4A and 4B illustrate plots of the polychromatic ray aberrationcurves over the half field of view and over the visible spectral bandranging 470 nm to 650 nm for a folded telephoto lens system asillustrated in FIGS. 3A and 3B.

FIGS. 5A and 5B are cross-sectional illustrations of another exampleembodiment of a compact telephoto camera including a folded telephotolens system that includes four refractive lens elements and a prism thatacts to fold the optical path.

FIGS. 6A and 6B illustrate plots of the polychromatic ray aberrationcurves over the half field of view and over the visible spectral bandranging 470 nm to 650 nm for a folded telephoto lens system asillustrated in FIGS. 5A and 5B.

FIGS. 7A and 7B are cross-sectional illustrations of another exampleembodiment of a compact telephoto camera including a folded telephotolens system that includes four lens elements with refractive power and afold mirror that acts to fold the optical path.

FIGS. 8A and 8B illustrate plots of the polychromatic ray aberrationcurves over the half field of view and over the visible spectral bandranging 470 nm to 650 nm for a folded telephoto lens system asillustrated in FIGS. 7A and 7B.

FIGS. 9A and 9B are cross-sectional illustrations of another exampleembodiment of a compact telephoto camera including a folded telephotolens system that includes four lens elements with refractive power and aprism that acts to fold the optical path.

FIGS. 10A and 10B illustrate plots of the polychromatic ray aberrationcurves over the half field of view and over the visible spectral bandranging 470 nm to 650 nm for a folded telephoto lens system asillustrated in FIGS. 9A and 9B.

FIGS. 11A and 11B are cross-sectional illustrations of another exampleembodiment of a compact camera including a folded telephoto lens systemthat includes four lens elements with refractive power and a prism thatacts to fold the optical path.

FIGS. 12A and 12B illustrate plots of the polychromatic ray aberrationcurves over the half field of view and over the visible spectral bandranging 470 nm to 650 nm for a folded telephoto lens system asillustrated in FIGS. 11A and 11B.

FIGS. 13A and 13B are cross-sectional illustrations of another exampleembodiment of a compact camera including a folded telephoto lens systemthat includes four lens elements with refractive power and a prism thatacts to fold the optical path.

FIGS. 14A and 14B illustrate plots of the polychromatic ray aberrationcurves over the half field of view and over the visible spectral bandranging 470 nm to 650 nm for a folded telephoto lens system asillustrated in FIGS. 13A and 13B.

FIG. 15A is a cross-sectional illustration of a compact camera includinga variation of the folded telephoto lens system of FIGS. 13A and 13B.

FIGS. 15B and 15C illustrate plots of the polychromatic ray aberrationcurves over the half field of view and over the visible spectral bandranging 470 nm to 650 nm for the folded telephoto lens system asillustrated in FIG. 15A in which the first surface of the first lenselement is a conic surface.

FIG. 16A is a cross-sectional illustration of a compact camera includinganother variation of the folded telephoto lens system of FIGS. 13A and13B.

FIGS. 16B and 16C illustrate plots of the polychromatic ray aberrationcurves over the half field of view and over the visible spectral bandranging 470 nm to 650 nm for the folded telephoto lens system asillustrated in FIG. 16A in which the first surface of the first lenselement is spherical.

FIGS. 17A and 17B are cross-sectional illustrations of another exampleembodiment of a compact camera including a folded telephoto lens systemthat includes four lens elements with refractive power and a fold mirrorthat acts to fold the optical path.

FIGS. 18A and 18B illustrate plots of the polychromatic ray aberrationcurves over the half field of view and over the visible spectral bandranging 470 nm to 650 nm for a folded telephoto lens system asillustrated in FIGS. 17A and 17B.

FIGS. 19A and 19B are cross-sectional illustrations of another exampleembodiment of a compact camera including a folded telephoto lens systemthat includes four lens elements with refractive power in which thefirst lens element is plano-convex in shape and in which the aperturestop is located at the first lens element and behind the front vertex ofthe lens system.

FIGS. 20A and 20B illustrate plots of the polychromatic ray aberrationcurves over the half field of view and over the visible spectral bandranging 470 nm to 650 nm for a folded telephoto lens system asillustrated in FIGS. 19A and 19B.

FIGS. 21A and 21B are cross-sectional illustrations of another exampleembodiment of a compact camera including a folded telephoto lens systemthat includes four lens elements with refractive power in which thefirst lens element is plano-convex in shape and in which the aperturestop is located between the first and second lens elements.

FIGS. 22A and 22B illustrate plots of the polychromatic ray aberrationcurves over the half field of view and over the visible spectral bandranging 470 nm to 650 nm for a folded telephoto lens system asillustrated in FIGS. 21A and 21B.

FIG. 23 is a high-level flowchart of a method for capturing images usinga camera including a folded telephoto lens system as illustrated inFIGS. 1A through 22B, according to at least some embodiments.

FIG. 24 illustrates an example computer system that may be used inembodiments.

This specification includes references to “one embodiment” or “anembodiment.” The appearances of the phrases “in one embodiment” or “inan embodiment” do not necessarily refer to the same embodiment.Particular features, structures, or characteristics may be combined inany suitable manner consistent with this disclosure.

“Comprising.” This term is open-ended. As used in the appended claims,this term does not foreclose additional structure or steps. Consider aclaim that recites: “An apparatus comprising one or more processor units. . . ”. Such a claim does not foreclose the apparatus from includingadditional components (e.g., a network interface unit, graphicscircuitry, etc.).

“Configured To.” Various units, circuits, or other components may bedescribed or claimed as “configured to” perform a task or tasks. In suchcontexts, “configured to” is used to connote structure by indicatingthat the units/circuits/components include structure (e.g., circuitry)that performs those task or tasks during operation. As such, theunit/circuit/component can be said to be configured to perform the taskeven when the specified unit/circuit/component is not currentlyoperational (e.g., is not on). The units/circuits/components used withthe “configured to” language include hardware—for example, circuits,memory storing program instructions executable to implement theoperation, etc. Reciting that a unit/circuit/component is “configuredto” perform one or more tasks is expressly intended not to invoke 35U.S.C. §112, sixth paragraph, for that unit/circuit/component.Additionally, “configured to” can include generic structure (e.g.,generic circuitry) that is manipulated by software and/or firmware(e.g., an FPGA or a general-purpose processor executing software) tooperate in manner that is capable of performing the task(s) at issue.“Configure to” may also include adapting a manufacturing process (e.g.,a semiconductor fabrication facility) to fabricate devices (e.g.,integrated circuits) that are adapted to implement or perform one ormore tasks.

“First,” “Second,” etc. As used herein, these terms are used as labelsfor nouns that they precede, and do not imply any type of ordering(e.g., spatial, temporal, logical, etc.). For example, a buffer circuitmay be described herein as performing write operations for “first” and“second” values. The terms “first” and “second” do not necessarily implythat the first value must be written before the second value.

“Based On.” As used herein, this term is used to describe one or morefactors that affect a determination. This term does not forecloseadditional factors that may affect a determination. That is, adetermination may be solely based on those factors or based, at least inpart, on those factors. Consider the phrase “determine A based on B.”While in this case, B is a factor that affects the determination of A,such a phrase does not foreclose the determination of A from also beingbased on C. In other instances, A may be determined based solely on B.

DETAILED DESCRIPTION

Embodiments of small form factor cameras including a photosensor and acompact folded telephoto lens system are described. Various embodimentsof a compact folded telephoto lens system including four lens elementsare described that may be used in the camera and that provide a largerimage and with longer effective focal length than has been realized inconventional compact cameras. The camera may be implemented in a smallpackage size while still capturing sharp, high resolution images, makingembodiments of the camera suitable for use in small and/or mobilemultipurpose devices such as cell phones, smartphones, pad or tabletcomputing devices, laptop, netbook, notebook, subnotebook, ultra bookcomputers, surveillance devices, and so on. However, note that theaspects of the camera (e.g., the lens system and photosensor) may bescaled up or down to provide cameras with larger or smaller packagesizes. In addition, embodiments of the camera system may be implementedas stand-alone digital cameras. In addition, to still (single framecapture) camera applications, embodiments of the camera system may beadapted for use in video camera applications.

Several example embodiments of compact folded telephoto lens systems aredescribed, including embodiments with a plane mirror or a prism and fourrefracting lens elements. FIGS. 1A-1B, 3A-3B, 7A-7B, and 17A-17B showvariations on an example embodiment that includes a plane mirror elementfor folding the light optical path and four refracting lens elements.FIGS. 5A-5B, 9A-9B, 11A-11B, 13A-13B, 19A-19B, and 21A-21B showvariations on an example embodiment that includes a prism for foldingthe light optical path and four refracting lens elements. Note, however,that these examples are not intended to be limiting, and that variationson the various parameters given for the lens system are possible whilestill achieving similar results.

The refractive lens elements in the various embodiments may be composedof plastic materials. In at least some embodiments, the refractive lenselements may be composed of injection molded plastic material. The foldmirror and prism elements in the various embodiments may be composed ofglass or plastic materials. However, other transparent optical materialsmay be used. Also note that, in a given embodiment, different ones ofthe lens elements may be composed of materials with different opticalcharacteristics, for example different Abbe numbers and/or differentrefractive indices. Also note that, while the lens elements in thevarious embodiments are generally illustrated as being circular lenses,in some embodiments one or more of the lenses may be of other shapes,for example oval, rectangular, square, or rectangular with roundedcorners.

In each of the example cameras illustrated in the Figures, the examplecamera includes at least a folded telephoto lens system and aphotosensor. The photosensor may be an integrated circuit (IC)technology chip or chips implemented according to any of various typesof photosensor technology. Examples of photosensor technology that maybe used are charge-coupled device (CCD) technology and complementarymetal-oxide-semiconductor (CMOS) technology. In at least someembodiments, pixel size of the photosensor may be 1.2 microns or less,although larger pixel sizes may be used. In a non-limiting exampleembodiment, the photosensor may be manufactured according to a 1280×720pixel image format to capture 1 megapixel images. However, other largeror smaller pixel formats may be used in embodiments, for example 5megapixel, 10 megapixel, or larger or smaller formats.

The camera may also include a frontal aperture stop (AS) located infront of (i.e., on the object side of) a first lens element. While FIGS.3A, 5A, 7A, 9A, 17A, and 19A show the frontal aperture stop located ator near the front vertex of the lens system, location of the aperturestop may be closer to or farther away from the vertex of the lenselement. Further, in some embodiments, the aperture stop may be locatedelsewhere in the folded telephoto lens system. For example, the aperturestop may be located between the first and second lens elements as shownin FIGS. 11A, 13A, and 21A.

The camera may also, but does not necessarily, include an infrared (IR)filter located between a last lens element of the telephoto lens systemand the photosensor. The IR filter may, for example, be composed of aglass material. However, other materials may be used. Note that the IRfilter does not affect the effective focal length f of the telephotolens system. Further note that the camera may also include othercomponents than those illustrated and described herein.

In the camera, the folded telephoto lens system forms an image at animage plane (IP) at or near the surface of the photosensor. The imagesize for a distant object is directly proportional to the effectivefocal length f of a lens system. The total track length (TTL) of thetelephoto lens system is the distance on the optical axis (AX) betweenthe front vertex at the object side surface of the first (object side)lens element and the image plane. For a telephoto lens system, the totaltrack length (TTL) is less than the lens system effective focal length(f), and the ratio of the total track length to the focal length (TTL/f)is the telephoto ratio. To be classified as a telephoto lens system,TTL/f is less than or equal to 1.

In a folded telephoto lens system, the light path folding element (e.g.a mirror or prism) with a reflecting surface changes a direction of theincoming light from a first optical axis (AX1) to a second optical axis(AX2). The incoming light from the object field passes through therefracting optical surfaces of the optical elements located on a firstoptical axis, AX1. A reflecting surface changes the direction of theincoming light from the first optical axis AX1 to a second optical axis,AX2, and the incoming light on the second optical axis passes throughthe refracting elements to the image plane on the second optical axis.The second optical axis AX2 may be oriented at an angle by thereflecting surface of the fold mirror or prism relative to the firstoptical axis AX1 to accommodate a desired compact form factor camerasystem. The angle may generally be 90 degrees to thus provide a rightangle fold of the optical axis, but other angles less than or greaterthan 90 degrees may be used in some embodiments. In the followingdiscussion, the total track length of the folded telephoto lens system(TTL) may be defined to be equal to the sum of the distance on AX1between the front vertex at the object side surface of the first (objectside) lens element and the reflecting surface of the fold mirror orprism (track length 1, denoted by TL1), and the distance on AX2 betweenthe reflecting surface of the fold mirror or prism to the image planedenoted (track length 2, denoted by TL2); i.e., TTL=TL1+TL2. Due to thechange in algebraic sign of the parameters following a reflectingsurface, the absolute value of the distance TL2 will be used todetermine the TTL in the above-mentioned definition.

In at least some embodiments, the folded telephoto lens system may be afixed telephoto lens system configured such that the effective focallength f of the lens system is at or about 14 millimeters (mm), theF-number (focal ratio, or f/#) is 2.8, the field of view (FOV) is at orabout 26 degrees (although narrower or wider FOVs may be achieved), andthe total track (TTL) is within the range of about 10 mm to about 14 mm.More generally, the telephoto lens system may be configured such thatthe telephoto ratio (TTL/f) satisfies the relation:

0.80<|TTL/f|≦1.0.

However, note that in some embodiments a folded lens system may beconfigured or may be adjustable so that the telephoto ratio is greaterthan one (|TTL/f|>1.0), and thus embodiments may encompass non-telephotofolded lens systems and/or folded lens systems that are adjustablebetween the telephoto range and the non-telephoto range. In at leastsome embodiments, the folded telephoto lens system may be configuredsuch that the effective focal length f of the lens system is 14 mm atreference wavelength 555 nm and the F-number is 2.8. The lens systemmay, for example, be configured with focal length f of 14 mm andF-number of 2.8 to satisfy specified optical, imaging, and/or packagingconstraints for particular camera system applications. Note that theF-number, also referred to as the focal ratio or f/# is defined by f/D,where D is the diameter of the entrance pupil, i.e., the effectiveaperture. As an example, at f=14 mm, an F-number of 2.8 is achieved withan effective aperture of 5.0 mm. At least some embodiments may also beconfigured with a field of view (FOV) at or about 26 degrees. In exampleembodiments, total track length (TTL) may vary from about 13.6 mm toabout 14 mm. In example embodiments, telephoto ratio (TTL/J) may varywithin the range of about 0.97 to about 1.0.

However, note that the focal length f, F-number, and/or other parametersmay be scaled or adjusted to meet various specifications of optical,imaging, and/or packaging constraints for other camera systemapplications. Constraints for a camera system that may be specified asrequirements for particular camera system applications and/or that maybe varied for different camera system applications include but are notlimited to the focal length f effective aperture, F-number, field ofview (FOV), imaging performance requirements, and packaging volume orsize constraints. For example, in an embodiment as illustrated in FIGS.1A and 1B, the folded telephoto lens system may be configured such thatthe effective focal length f of the lens system is 10 mm at referencewavelength 555 nm, F-number of 2.8 and with a field of view (FOV) at orabout 24 degrees. The total track length (TTL) of this exampleembodiment is about 8.8 mm and with a telephoto ratio (|TTL/f|) of about0.88.

In some embodiments, the folded telephoto lens system may be adjustable.For example, in some embodiments, a folded telephoto lens system asdescribed herein may include an adjustable iris (entrance) pupil oraperture stop. Using an adjustable aperture stop, the F-number (focalratio, or f#) may be dynamically varied within a range. For example, ifthe lens is well-corrected at f/2.8, at a given focal length f and FOV,then the focal ratio may be varied within the range of 2.8 to 10 (orhigher) by adjusting the aperture stop, assuming that the aperture stopcan be adjusted to the desired F-number setting. In some embodiments,the lens system may be used at faster focal ratios (f#<2.8) by adjustingthe aperture stop with degraded image quality performance at the sameFOV (e.g. 26 degrees), or with reasonably good performance at a smallerFOV.

In some embodiments, the folded telephoto lens system may also include amanual and/or automatic focusing mechanism to provide zoomingcapabilities for focusing an object scene at infinity (object scenedistance from camera ≧20 meters) to near object distance (≦1 meter). Forexample, in some embodiments, folded telephoto lens systems as describedherein (see FIGS. 3A, 5A, and 7A) may include an adjustable focusingmechanism to translate or move a group of lens elements to focus objectsat distances ranging from infinity (≧20 meters) to (≦1 meter). In someembodiments, the folded telephoto lens system (see FIGS. 13A, 17A, 19A,and 21A) may include an adjustable focus mechanism via which thephotosensor at the image plane may be zoomed or moved or actuated forfocusing an object scene at distances ranging from greater than 20meters to less than 1 meter. Note that some embodiments may beconfigured to move or translate the photosensor and one or more lenselements to achieve focus.

While ranges of values may be given herein as examples for adjustablecameras and folded telephoto lens systems in which one or more opticalparameters may be dynamically varied (e.g., using an adjustable aperturestop and/or adjustable focus), embodiments of camera systems thatinclude fixed (non-adjustable) folded telephoto lens systems in whichvalues for optical and other parameters are within these ranges may beimplemented.

Referring first to embodiments as illustrated in FIGS. 1A-1B, 3A-3B,7A-7B, and 17A-17B, a compact folded telephoto lens system (110, 210,410, or 810) of a camera (100. 200, 400, or 800) may include a lightpath folding element (e.g., a mirror), four lens elements (101-104 inlens system 110 of FIGS. 1A-1B, 201-204 in lens system 210 of FIGS.3A-3B, 401-404 in lens system 410 of FIGS. 7A-7B, and 801-804 in lenssystem 810 of FIGS. 17A-17B) with refractive power, and lens systemfocal length off arranged along a folded optical axis AX from an objectside (AX1) to an image side (AX2):

-   -   a first lens element L1 (101, 201, 401, or 801) with positive        refractive power having a convex object side surface;    -   a second lens element L2 (102, 202, 402, or 802) with negative        refractive power;    -   a light path folding mirror (130, 230, 430, or 830) that folds        the optical axis from AX1 to AX2;    -   a third lens element L3 (103, 203, 403, or 803) with negative        refractive power; and    -   a fourth lens element L4 (104, 204, 404, or 804) with positive        refractive power.

In addition, in at least some embodiments, at least one of the objectside and image side surfaces of at least one of the four lens elementsis aspheric. In addition, at least some embodiments may include an IRfilter, for example located between the fourth lens element and thephotosensor.

The lens systems 110, 210, 410, and 810 may be configured such that thetelephoto ratio (TTL/f) satisfies the relation:

0.8<|TTL/f|≦1.0.  (1)

The first lens element L1 of the lens system 110, 210, 410, and 810 mayhave positive refractive power and focal length f1 and may satisfy therelation:

0.4<|f1/f|<0.8.  (2)

In at least some embodiments of the lens system 110, 210, 410, and 810,L1 may have a shape with vertex radii of curvature R1 and R2 and withshape satisfying the condition,

0≦|R1/R2|<6.1,  (3)

where R1 is an object side vertex radius of L1, and R2 is an image sidevertex radius of curvature of L1.

The first lens element L1 may have a positive refractive power and mayhave a positive meniscus or biconvex in shape. An example embodimentwhere L1 is a positive meniscus in shape and having a convex object sidesurface is illustrated by the lens element L1 in folded telephoto lenssystem 410 of FIG. 7A. An example embodiment where L1 is biconvex inshape is illustrated by the lens element L1 in lens system 810 of FIG.17A.

The lens systems 110, 210, 410, and 810 may be configured such that thedioptric power distribution of the lens elements L2, L3, and L4 may haverefractive powers or focal lengths f2, f3, and f4, and may satisfy thefollowing conditions:

0.5<|f2/f<1.5, and 0.02<|R3/R4|<3.3,  (4)

0.4<|f3/f|<2.0, and 0.05<|R5/R6|<12.1,  (5)

0.5<|f4/f|<10.0, and 0.04<|R7/R8|<1.1,  (6)

where:

-   -   R3 is an object side surface vertex radius of curvature of the        second lens element L2 and R4 is the vertex radius of curvature        of an image side surface of L2;    -   R5 is the vertex radius of curvature of an object side surface        of the third lens element L3 and R6 is the vertex radius of        curvature of an image side surface of L3; and    -   R7 is the vertex radius of curvature of an object side surface        of the fourth lens element L4 and R8 is the vertex radius of        curvature of an image side surface of L4.

The second lens element L2 may have a negative refractive power and maybe a negative meniscus in shape. An example embodiment where L2 is anegative meniscus in shape and having a convex object side surface isillustrated by the lens element L2 in folded telephoto lens system 110of FIG. 1A.

The third lens element L3 may have a negative refractive power and maybe a negative meniscus in shape. Example embodiments where L3 is anegative meniscus in shape and having a convex object side surface isillustrated by the lens element L3 in folded telephoto lens systems 210of FIG. 3A, and lens system 410 of FIG. 7A.

The fourth lens element L4 may have a positive refractive power and maybe a positive meniscus or biconvex in shape. Example embodiments whereL4 is a positive meniscus in shape and having a convex object sidesurface is illustrated by the lens element L4 in folded telephoto lenssystems 810 of FIG. 17A. An example embodiment where L4 is biconvex inshape is illustrated by the lens element L4 in folded telephoto lenssystem 110 of FIG. 1A.

In at least some embodiments of lens systems 110, 210, 410, and 810, thefirst lens element L1, and the third lens element L3 may be composed ofa material (e.g., a plastic material) having an Abbe number of V1. Thesecond, and fourth lens elements L2 and L4 may be composed of a material(e.g., plastic material) having an Abbe number of V2. The Abbe numbersof the lens materials for the lens elements may satisfy the condition:

30<V1−V2<35.  (7)

In at least some embodiments of lens systems 110, 210, 410, and 810, thelens element L1 and L2 may be arranged in close proximity such that thecombination of L1 and L2 may be considered as an air-spaced doublet lensL12 of positive refractive power or positive focal length f12. In atleast some embodiments of lens systems 110, 210, 410, and 810, the lenselement L3 and L4 may be arranged in close proximity such that thecombination of L3 and L4 may be considered as an air-spaced doublet lensL34 having negative refractive power or negative focal length f34.

Referring now to embodiments as illustrated in FIGS. 5A-5B, 9A-9B,11A-11B, 13A-13B, 19A-19B, and 21A-21B a compact folded telephoto lenssystem (310, 510, 610, 710, 910 or 1010) of a camera (300. 500, 600,700, 900 or 1000) may include a light path folding element and four lenselements (301-304 in lens system 310 of FIG. 5A, 501-504 in lens system510 of FIG. 9A, 601-604 in lens system 610 of FIG. 11A, 701-704 in lenssystem 710 of FIG. 13A, 901-904 in FIG. 19A, 1001-1004 in lens system1010 of FIG. 21A) with refractive power, and lens system focal lengthoff, arranged along a folded optical axis AX from an object side (AX1)to an image side (AX2):

-   -   a first lens element L1 (301, 501, 601, 701, 901 or 1001) with        positive refractive power having a convex object side surface;    -   a second lens element L2 (302, 502, 602, 702, 902, or 1002) with        negative refractive power having a convex object side surface;    -   a light path folding prism (340, 540, 640, 740, 940 or 1040)        that folds the optical axis from AX1 to AX2;    -   a third lens element L3 (303, 503, 603, 703, 903 or 1003) with        negative refractive power; and    -   a fourth lens element L4 (304, 504, 604, 704, 904 or 1004) with        positive refractive power.

In addition, in at least some embodiments, at least one of the objectside and image side surfaces of at least one of the four lens elementsis aspheric. In addition, at least some embodiments may include an IRfilter, for example located between the fourth lens element and thephotosensor.

The lens systems 310, 510, 610, 710, 910, and 1010 are configured suchthat the telephoto ratio (TTL/f) satisfies the relation (1) given by:

0.8<|TTL/f<1.0.

Moreover, the lens systems 310, 510, 610, 710, 910, and 1010 areconfigured such that the refractive power distribution of the lenselements L1, L2, L3, and L4, as well as the vertex radii of curvature ofthe lens elements, satisfy the relations given by conditions (2), (3),(4), (5), and (6).

The first lens element L1 may have a positive refractive power and mayhave a biconvex or plano-convex in shape. Example embodiments where L1is biconvex in shape are illustrated by the lens elements 501 and 601 inlens system 510 of FIG. 9A and lens system 610 of FIG. 11A,respectively. Two example embodiments where L1 is plano-convex in shapeare illustrated by lens element 901 and 1001 in lens systems 910 and1010 of FIGS. 19A and 21A, respectively.

The second lens element L2 may have a negative refractive power and maybe a negative meniscus in shape. Example embodiments where L2 is anegative meniscus in shape and having a convex object side surface isillustrated by the lens element L2 in folded telephoto lens systems 510of FIG. 9A, 610 of FIG. 11A, 710 of FIG. 13A, 910 of FIG. 19A, and 1010of FIG. 21A.

The fourth lens element L4 may have a positive refractive power and maybe a positive meniscus or biconvex in shape. Example embodiments whereL4 is a positive meniscus in shape and having a convex object sidesurface is illustrated by the lens element L4 in folded telephoto lenssystems 910 of FIG. 19A and 1010 of FIG. 21A. An example embodimentwhere L4 is biconvex in shape is illustrated by the lens element L4 infolded telephoto lens system 710 of FIG. 13A.

In at least some embodiments of lens systems 310, 510, 610, 710, 910,and 1010, the first lens element L1, and the third lens element L3 maybe composed of a material (e.g., a plastic material) having an Abbenumber of V1. The second, and fourth lens elements L2 and L4 may becomposed of a material (e.g., plastic material) having an Abbe number ofV2. The Abbe numbers of the lens materials for the lens elements maysatisfy the condition (7):

30<V1−V2<35.

In at least some embodiments of lens systems 310, 510, 610, 710, 910,and 1010, the lens element L1 and L2 may be arranged in close proximitysuch that the combination of L1 and L2 may be considered as anair-spaced doublet lens L12 of positive refractive power or positivefocal length f12. In at least some embodiments of lens systems 310, 510,610, 710, and 1010, the lens element L3 and L4 may be arranged in closeproximity such that the combination of L3 and L4 may be considered as anair-spaced doublet lens L34 having negative refractive power or negativefocal length f34.

The following provides further details of various embodiments of acompact folded telephoto lens system that may be used in a small formfactor telephoto camera in reference to FIGS. 1A through 22B.

FIGS. 1A and 1B are cross-sectional illustrations of an exampleembodiment of a compact telephoto camera 100 including a compact foldedtelephoto lens system 110. Lens system 110 includes four lens elements(101-104) with refractive power. Arranged along an optical axis AX ofthe camera 100 from an object side (AX1) to an image side (AX2) are afirst lens element L1 (101) with positive refractive power having aconvex object side surface and focal length f1, an aperture stop AS, asecond lens element L2 (102) with negative refractive power having aconvex object side surface and focal length f2, a planar fold mirror 130that is oriented to change the direction of the incoming light path andthus to fold the optical axis from AX1 to AX2, a third lens element L3(103) with negative refractive power and focal length f3, and a fourthlens element L4 (104) with positive refractive power having a conveximage side surface and focal length f4. The lens system 110 forms animage at the surface of a photosensor 120. In some embodiments, aninfrared (IR) filter may be located between the fourth lens element L4and the photosensor 120.

The effective focal length of the lens system 110 is given by f. Thetotal track length (TTL) of the compact folded telephoto lens system 110is the distance along the optical axes AX1 and AX2 between the objectside surface of the first element L1 and the image plane. Referring toFIGS. 1A and 1B, the TTL is the sum of TL1 and TL2, where TL1 is theaxial distance between the front vertex of the object side surface of L1and the reflecting surface of the fold mirror 130, and TL2 is the axialdistance between the reflecting surface of fold mirror 130 and the imageplane. The lens system 110 is configured such that the telephoto ratio(TTL/f) of the lens system 110 satisfies the relation:

0.8<|TTL/f|≦1.0.

An aperture stop AS, which may be located at the front surface of lenselement L1, determines the entrance pupil of the lens system 110. Thelens system 110 focal ratio of f-number f# is defined as the lens system110 effective focal length f divided by the entrance pupil diameter. TheIR filter may act to block infrared radiation that could damage oradversely affect the photosensor, and may be configured so as to have noeffect on f.

Tables 1A-1D provide example values for various optical and physicalparameters of an example embodiment of a camera 100 and lens system 110as illustrated in FIGS. 1A and 1B. Table 1A-1D may be referred to asproviding an optical prescription for the lens system 110.

Referring to Tables 1A-1D, embodiments of lens system 110 coverapplications in the visible region of the spectrum from 470 nanometers(nm) to 650 nm with reference wavelength at 555 nm. The opticalprescription in Tables 1A-1D provides high image quality at f/2.8 over470 nm to 650 nm spectrum, for an effective focal length f of 10millimeters (mm), covering 24 degrees field of view (FOV) (12 degreeshalf FOV). The folded telephoto lens system 110, illustrated in FIGS. 1Aand 1B and with optical prescription as shown in Tables 1A-1D, has totaltrack length (TTL=TL1+TL2) of 8.8 mm and a telephoto ratio (TTL/f) of0.88.

The four lens elements L1, L2, L3, and L4 of lens system 110 may becomposed of plastic materials with refractive indices and Abbe numbersas listed in Table 1B. As shown in Table 1B, in at least someembodiments of lens system 110, two types of plastic materials may beused for the lens elements. Lens element L1 and L3 may be composed ofthe same plastic material with an Abbe number V1 of 56.1, and lenselements L2 and L4, may be composed of another plastic material with anAbbe number V2 of 23.3. The application of these two plastic materialsfor the lens elements in lens system 110 enables lens system 110 to beoptimized and corrected for chromatic aberrations over the visibleregion. The lens element materials may be chosen and the refractivepower distribution of the lens elements may be calculated to satisfy theeffective focal length f and correction of the field curvature orPetzval sum. The monochromatic and chromatic variations of opticalaberrations may be reduced by adjusting the radii of curvature andaspheric coefficients or geometrical shapes of the lens elements andaxial separations as illustrated in Table 1C to produce well-correctedand balanced minimal residual aberrations. FIG. 2 illustrates a plot ofthe polychromatic ray aberration curves over the half field of view(HFOV=12 degrees) over the visible spectral band ranging from 470 nm to650 nm for a folded telephoto lens system 110 as illustrated in FIGS. 1Aand 1B and described in Tables 1A-1D.

The optical prescription in Tables 1A-1D describes an example embodimentof a compact folded telephoto lens system 110 as illustrated in FIGS. 1Aand 1B that includes four lens elements with refractive power andeffective focal length f, and in which a second lens element L2 hasnegative refractive power or negative focal length f2 and a convexobject side surface. In addition, lens element L2 of lens system 110 isnegative meniscus in shape and has positive vertex radii of curvature R3and R4, where R3>R4, and R3/R4 is about 2.865.

In the example embodiment of lens system 110 as described by the opticalprescription in Tables 1A-1D, the refractive powers of the lens elementsare distributed such that the ratios of the focal lengths of the lenselements relative to the system focal length f are |f1/f|=0.430,|f2/f|=0.570, |f3/f|=0.471, and |f4/f|=0.671. Lens element L1 is abiconvex lens with vertex radii of curvature R1/R2=−0.061, and L2 hasvertex radii of curvature R3/R4=2.865. Lens element L3 has vertex radiiof curvature R5/R6=12.00, and lens element L4 is biconvex in shape withvertex radii of curvature R7/R8=−0.561. The aspheric coefficients forthe surfaces of the lens elements in lens system 110 in the exampleembodiment are listed in Table 1C. Configuring lens system 110 accordingto the arrangement of the power distribution of the lens elements, andadjusting the radii of curvature and aspheric coefficient as shown inTables 1A-1D, the total track length (TTL), of the lens system 110 maybe reduced (e.g., to 8.8 mm as shown in Table 1A) and aberration of thesystem may effectively be corrected to obtain optical performance ofhigh image quality resolution in a small form factor camera 100.

FIGS. 3A and 3B are cross-sectional illustrations of another exampleembodiment of a compact telephoto camera 200 including a compact foldedtelephoto lens system 210. Lens system 210 includes four lens elements(201-204) with refractive power. Lens system 210 may be viewed as avariation of lens system 110 of FIGS. 1A and 1B and elements of the twosystems 110 and 210 may be similar. However, in lens system 210, thethird element L3 (203) is a negative meniscus lens with convex objectside surface.

Tables 2A-2E provide example values of various optical and physicalparameters of an example embodiment of a camera 200 and lens system 210as illustrated in FIGS. 3A and 3B. In at least some embodiments, system210 may include a zooming mechanism for dynamically focusing an objectscene from infinity (object distance ≧20 meters) to near objectdistance, <500 mm. Tables 2A-2E may be referred to as providing anoptical prescription for a zoom lens system 210. In this exampleembodiment, lens system 210 may include a focusing lens group GR1including lens elements L1 and L2 that may be translated or actuated,together with the aperture stop along AX1, for focusing an object scenelocated at <500 mm. The zoom parameters for system 210 are listed inTable 2E. The zoom parameters shown in Table 2E for position 1 are theaxial thickness or space separation on surface #7 (along AX1) betweenlens element L2 from the fold mirror 230 when the object scene distanceis at infinity (the optical prescription as listed in Table 2B). Thecorresponding optical prescription for an object scene at 500 mm(position 2) is the same as the prescription listed in Table 2B, exceptthat the object distance in surface #0 is replaced by 500 mm, and thespace separation of L2 on surface #7 is replaced by 0.7756 mm. As shownin Table 2E, the lens group GR1 moves by about 0.316 mm for the lenssystem 210 to zoom and focus object scene from >20 meters away from thecamera to near object scene at <500 mm distance.

The optical prescription in Tables 2A-2E is for a zoom lens system 210with an effective focal length f of 14 mm at 555 nm wavelength, a focalratio of f/2.8, with 19 degrees FOV, TTL of 13.6 mm, and with TTL/fequal to 0.971. Lens system 210 is a compact folded imaging systemdesigned for visible spectrum covering 470 nm to 650 nm.

The lens elements L1, L2, L3, and L4 of lens system 210 may be composedof plastic materials with refractive indices and Abbe numbers as listedin Table 2B. In this example embodiment of lens system 210, the choiceof lens materials are the same as in the optical prescription for thelens system 110 as listed in Tables 1A-1D. Referring to the lens system210, the lens element L1 and L3 may be composed of a plastic materialhaving an Abbe number of V1=56.1. The lens elements L2 and L4 may becomposed of a plastic material with Abbe number V2=23.3.

Lens system 210 as specified in Tables 2A-2E is configured to correctoptical aberrations as described in reference to lens system 110 andTables 1A-1D. FIGS. 4A and 4B illustrate plots of the polychromatic rayaberration curves over the half field of view (HFOV=9.5 degrees) for anobject point on-axis (at 0 degrees) to an off-axis field point at 9.5degrees, and over the visible band ranging from 470 nm to 650 nm for acompact folded telephoto lens system 210 as illustrated in FIGS. 3A and3B and described in Tables 2A-2E. Note that the plots illustrated inFIGS. 4A and 4B show the well-corrected aberrations for both focuspositions 1 and 2 (i.e., the optical performance of lens system 210 foran object scene located at infinity, and for an object scene located at<500 mm distance).

The optical prescription in Tables 2A-2E describes an example embodimentof a folded telephoto lens system as illustrated in FIGS. 3A and 3B thatincludes four lens elements with refractive power and effective focallength f, and with refractive powers of the lens elements distributedsuch that the ratios of the focal lengths of the lens elements relativeto the system focal length f are |f1/f|=0.518, |f2/f|=1.09,|f3/f|=1.214, and |f4/f|=9.552. Lens element L1 is a biconvex lens withvertex radii of curvature R1/R2=−0.145, and L2 has vertex radii ofcurvature R3/R4=−0.026. Lens element L3 is negative meniscus in shapeand has vertex radii of curvature R5/R6=1.530, and lens element L4 withvertex radii of curvature R7/R8=1.040. The aspheric coefficients for thesurfaces of the lens elements in lens system 210 in the exampleembodiment are listed in Table 2C. Configuring lens system 210 accordingto the arrangement of the power distribution of the lens elements, andadjusting the radii of curvature and aspheric coefficient as shown inTables 2A-2E, the total track length (TTL), of the lens system 210 maybe reduced (e.g., to 13.6 mm as shown in Table 2A) and aberration of thesystem may effectively be corrected to obtain optical performance ofhigh image quality resolution, for an object scene at infinity and foran object scene located <500 mm distance, in a small form factor camera200.

FIGS. 5A and 5B are cross-sectional illustrations of another exampleembodiment of a compact telephoto camera 300 including a compact foldedtelephoto lens system 310. Lens system 310 includes four lens elements(301-304) with refractive power. Arranged along an optical axis AX ofthe camera 300 from an object side (AX1) to an image side (AX2) are afirst lens element L1 (301) with positive refractive power having aconvex object side surface and focal length f1, an aperture stop AS, asecond lens element L2 (302) with negative refractive power and focallength f2, a prism 340 oriented to change the direction of the incominglight path and thus to fold the optical axis from AX1 to AX2, a thirdlens element L3 (303) with negative refractive power and focal lengthf3, and a fourth lens element L4 (304) with positive refractive powerhaving a convex object side surface and focal length f4. The lens system310 forms an image at the surface of a photosensor 320. In someembodiments, an infrared (IR) filter may be located between the fourthlens element L4 and the photosensor 320.

The effective focal length of the lens system 310 is given by f. Thetotal track length (TTL) of the compact folded telephoto lens system 310is the distance along the optical axes AX1 and AX2 between the objectside surface of the first element L1 and the image plane. Referring toFIGS. 5A and 5B, the TTL is the sum of the track lengths TL1 and TL2,where TL1 is the axial distance between the front vertex of the objectside surface of L1 and the reflecting surface of the prism 340, and TL2is the axial distance between the reflecting surface of PR and the imageplane. The lens system 310 is configured such that the telephoto ratio(TTL/f) of the lens system 310 satisfies the relation:

0.8<|TTL/f|≦1.0.

An aperture stop AS, which may be located at the front surface of lenselement L1, determines the entrance pupil of the lens system 310. Thelens system 310 focal ratio or f-number f# is defined as the lens system310 effective focal length f divided by the entrance pupil diameter. TheIR filter may act to block infrared radiation that could damage oradversely affect the photosensor, and may be configured so as to have noeffect on f.

Tables 3A-3E provide example values of various optical and physicalparameters of an example embodiment of a camera 300 and lens system 310as illustrated in FIGS. 5A and 5B. In at least some embodiments, system310 may include a zooming mechanism for dynamically focusing an objectscene from infinity (object distance ≧20 meters) to near objectdistance, <500 mm. Tables 3A-3E may be referred to as providing anoptical prescription for a zoom lens system 310. In this exampleembodiment, lens system 310 may include a focusing lens group GR1including lens elements L1 and L2 that may be translated or actuated,together with the aperture stop along AX1, for focusing an object scenelocated at <500 mm. The zoom parameters for system 310 are listed inTable 3E. The zoom parameters shown in Table 3E for position 1 are theaxial thickness or space separation on surface #7 (along AX1) of lenselement L2 from the reflecting surface of prism 340 when the objectscene distance is at infinity (the optical prescription as listed inTable 3B). The corresponding optical prescription for an object scene at500 mm (position 2) is the same as the prescription listed in Table 3B,except that the object distance in surface #0 is replaced by 500 mm, andthe space separation of L2 on surface #7 is replaced by 0.5841 mm. Asshown in Table 3E, the lens group GR1 moves by about 0.215 mm for thelens system 310 to zoom and focus object scene from >20 meters away fromthe camera to near object scene at <500 mm distance.

The optical prescription in Tables 3A-3E is for a zoom lens system 310with an effective focal length f of 14 mm at 555 nm wavelength, a focalratio of f/2.8, with 19 degrees FOV, TTL of 14.0 mm, and with TTL/fequal to 1.0. Lens system 310 is a compact folded imaging systemdesigned for visible spectrum covering 470 nm to 650 nm.

The lens elements L1, L2, L3, and L4 of lens system 310 may be composedof plastic materials with refractive indices and Abbe numbers as listedin Table 3B. In this example embodiment of lens system 310, the choiceof lens materials are the same as in the optical prescription for thelens system 110 as listed in Tables 1A-1D. Referring to the lens system310, the lens element L1 and L3 may be composed of a plastic materialhaving an Abbe number of V1=56.1. The lens elements L2 and L4 may becomposed of a plastic material with Abbe number V2=23.3.

Lens system 310 as specified in Tables 3A-3E is configured to correctoptical aberrations as described in reference to lens system 110 andTables 1A-1D. FIGS. 6A and 6B illustrate plots of the polychromatic rayaberration curves over the half field of view (HFOV=9.5 degrees) for anobject point on-axis (at 0 degrees) to an off-axis field point at 9.5degrees, and over the visible band ranging from 470 nm to 650 nm for acompact folded telephoto lens system 310 as illustrated in FIGS. 5A and5B and described in Tables 3A-3E. Note that the plots illustrated inFIGS. 6A and 6B show the well-corrected aberrations for both focuspositions 1 and 2 (i.e., the optical performance of lens system 310 foran object scene located at infinity, and for an object scene located at<500 mm distance).

The optical prescription in Tables 3A-3E describes an example embodimentof a folded telephoto lens system as illustrated in FIGS. 5A and 5B thatincludes four lens elements with refractive power and effective focallength f, and with refractive powers of the lens elements distributedsuch that the ratios of the focal lengths of the lens elements relativeto the system focal length f are |f1/f|=0.468, |f2/f|=1.09,|f3/f|=0.768, and |f4/f|=8.754. Lens element L1 is a biconvex lens withvertex radii of curvature R1/R2=−0.236, and L2 has vertex radii ofcurvature R3/R4=0.189. Lens element L3 has vertex radii of curvatureR5/R6=5.241, and lens element L4 with vertex radii of curvatureR7/R8=1.009. The aspheric coefficients for the surfaces of the lenselements in lens system 310 in the example embodiment are listed inTable 3C. Configuring lens system 310 according to the arrangement ofthe power distribution of the lens elements, and adjusting the radii ofcurvature and aspheric coefficient as shown in Tables 3A-3E, the totaltrack length (TTL), of the lens system 310 may be reduced (e.g., to 14.0mm as shown in Table 3A) and aberration of the system may effectively becorrected to obtain optical performance of high image qualityresolution, for an object scene at infinity and for an object scenelocated <500 mm distance, in a small form factor camera 300.

FIGS. 7A and 7B are cross-sectional illustrations of another exampleembodiment of a compact telephoto camera 400 including a foldedtelephoto lens system 410. Lens system 410 includes four lens elements(401-404) with refractive power. Lens system 410 may be viewed as avariation of lens system 210 of FIGS. 3A and 3B and the elements of thetwo systems 410 and 210 may be similar. However, in lens system 410, thefirst lens element L1 has positive refractive power or positive focallength f1 and has positive meniscus shape with convex object sidesurface.

Tables 4A-4E provide example values of various optical and physicalparameters of an example embodiment of a camera 400 and lens system 410as illustrated in FIGS. 7A and 7B. In at least some embodiments, system410 may include a zooming mechanism for dynamically focusing an objectscene from infinity (object distance ≧20 meters) to near objectdistance, <1 meter. Tables 4A-4E may be referred to as providing anoptical prescription for a zoom lens system 410. In this exampleembodiment, lens system 410 may include a focusing lens group GR1including lens elements L1 and L2 that may be translated or actuated,together with the aperture stop along AX1, for focusing an object scenelocated at <1 meter. The zoom parameters for system 410 are listed inTable 4E. The zoom parameters shown in Table 4E for position 1 are theaxial thickness or space separation on surface #7 (along AX1) betweenlens element L2 from the fold mirror 430 when the object scene distanceis at infinity (the optical prescription as listed in Table 4B). Thecorresponding optical prescription for an object scene at 1 meter(position 2) is the same as the prescription listed in Table 2B, exceptthat the object distance in surface #0 is replaced by 1000 mm, and thespace separation of L2 on surface #7 is replaced by 1.2608 mm. As shownin Table 4E, the lens group GR1 moves by about 0.203 mm for the lenssystem 410 to zoom and focus object scene from >20 meters away from thecamera to near object scene at <1 meter distance.

The optical prescription in Tables 4A-4E is for a zoom lens system 410with an effective focal length f of 14 mm at 555 nm wavelength, a focalratio of f/2.8, with 26 degrees FOV, TTL of 13.65 mm, and with TTL/fequal to 0.975. Lens system 410 is a compact folded imaging systemdesigned for visible spectrum covering 470 nm to 650 nm.

The lens elements L1, L2, L3, and L4 of lens system 410 may be composedof plastic materials with refractive indices and Abbe numbers as listedin Table 4B. In this example embodiment of lens system 410, the choiceof lens materials are the same as in the optical prescription for thelens system 110 as listed in Tables 1A-1D. Referring to the lens system410, the lens element L1 and L3 may be composed of a plastic materialhaving an Abbe number of V1=56.1. The lens elements L2 and L4 may becomposed of a plastic material with Abbe number V2=23.3.

Lens system 410 as specified in Tables 4A-4E is configured to correctoptical aberrations as described in reference to lens system 110 andTables 1A-1D. FIGS. 8A and 8B illustrate plots of the polychromatic rayaberration curves over the half field of view (HFOV=13.0 degrees) for anobject point on-axis (at 0 degrees) to an off-axis field point at 13.0degrees, and over the visible band ranging from 470 nm to 650 nm for acompact folded telephoto lens system 410 as illustrated in FIGS. 7A and7B and described in Tables 4A-4E. Note that the plots illustrated inFIGS. 8A and 8B show the well-corrected aberrations for both focuspositions 1 and 2 (i.e., the optical performance of lens system 410 foran object scene located at infinity, and for an object scene located at<1000 mm distance).

The optical prescription in Tables 4A-4E describes an example embodimentof a folded telephoto lens system as illustrated in FIGS. 7A and 7B thatincludes four lens elements with refractive power and effective focallength f, and with refractive powers of the lens elements distributedsuch that the ratios of the focal lengths of the lens elements relativeto the system focal length f are |f1/f|=0.510, |f2/f|=0.810,|f3/f|=1.534, and |f4/f|=3.145. Lens element L1 is positive meniscuslens with vertex radii of curvature R1/R2=0.102, and L2 is negativemeniscus lens with vertex radii of curvature R3/R4=1.628. Lens elementL3 is negative meniscus in shape and has vertex radii of curvatureR5/R6=1.596, and lens element L4 with vertex radii of curvatureR7/R8=0.848. The aspheric coefficients for the surfaces of the lenselements in lens system 410 in the example embodiment are listed inTable 4C. Configuring lens system 410 according to the arrangement ofthe power distribution of the lens elements, and adjusting the radii ofcurvature and aspheric coefficient as shown in Tables 4A-4E, the totaltrack length (TTL), of the lens system 410 may be reduced (e.g., to13.65 mm as shown in Table 4A) and aberration of the system mayeffectively be corrected to obtain optical performance of high imagequality resolution, for an object scene at infinity and for an objectscene located <1 meter distance, in a small form factor camera 400.

FIGS. 9A and 9B are cross-sectional illustrations of another exampleembodiment of a compact telephoto camera 500 including a foldedtelephoto lens system 510. Lens system 510 includes four lens elements(501-504) with refractive power. Lens system 510 may be viewed as avariation of lens system 310 of FIGS. 5A and 5B since the light pathfolding optical element is a prism 540 and the elements of the twosystems 510 and 310 may be similar. However, in lens system 510, thesecond lens element L2 has negative refractive power or negative focallength f2 and has negative meniscus shape with convex object sidesurface. Moreover, the first lens group GR1 (including L1 and L2) andthe second lens group GR2 (including L3 and L4) may have lens elementsin close proximity that may be considered as air-spaced doublets.

Tables 5A-5E provide example values of various optical and physicalparameters of an example embodiment of a camera 500 and lens system 510as illustrated in FIGS. 9A and 9B. In at least some embodiments, system510 may include a zooming mechanism for dynamically focusing an objectscene from infinity (object distance ≧20 meters) to near objectdistance, <1 meter. Tables 5A-5E may be referred to as providing anoptical prescription for a zoom lens system 510. In this exampleembodiment, lens system 510 may include a focusing lens group GR1including lens elements L1 and L2 that may be translated or actuated,together with the aperture stop along AX1, for focusing an object scenelocated at <1 meter. The zoom parameters for system 510 are listed inTable 5E. The zoom parameters shown in Table 5E for position 1 are theaxial thickness or space separation on surface #7 (along AX1) of lenselement L2 from the reflecting surface of prism 540 when the objectscene distance is at infinity (the optical prescription as listed inTable 5B). The corresponding optical prescription for an object scene at1 meter (position 2) is the same as the prescription listed in Table 5B,except that the object distance in surface #0 is replaced by 1000 mm,and the space separation of L2 on surface #7 is replaced by 0.9337 mm.As shown in Table 5E, the lens group GR1 moves by about 0.121 mm fromits nominal position 1 to position 2 for the lens system 510 to zoom andfocus object scene from >20 meters away from the camera to near objectscene at <1000 mm distance.

The optical prescription in Tables 5A-5E is for a zoom lens system 510with an effective focal length f of 14 mm at 555 nm wavelength, a focalratio of f/2.8, with 26 degrees FOV, TTL of 13.8 mm, and with TTL/fequal to 0.986. Lens system 510 is a compact folded imaging systemdesigned for visible spectrum covering 470 nm to 650 nm.

The lens elements L1, L2, L3, and L4 of lens system 510 may be composedof plastic materials with refractive indices and Abbe numbers as listedin Table 5B. In this example embodiment of lens system 510, the choiceof lens materials are the same as in the optical prescription for thelens system 110 as listed in Tables 1A-1D. Referring to the lens system510, the lens element L1 and L3 may be composed of a plastic materialhaving an Abbe number of V1=56.1. The lens elements L2 and L4 may becomposed of a plastic material with Abbe number V2=23.3.

Lens system 510 as specified in Tables 5A-5E is configured to correctoptical aberrations as described in reference to lens system 110 andTables 1A-1D. FIGS. 10A and 10B illustrate plots of the polychromaticray aberration curves over the half field of view (HFOV=13.0 degrees)for an object point on-axis (at 0 degrees) to an off-axis field point at13.0 degrees, and over the visible band ranging from 470 nm to 650 nmfor a compact folded telephoto lens system 510 as illustrated in FIGS.9A and 9B and described in Tables 5A-5E. Note that the plots illustratedin FIGS. 10A and 10B show the well-corrected aberrations for both focuspositions 1 and 2 (i.e., the optical performance of lens system 510 foran object scene located at infinity, and for an object scene located at<1000 mm distance).

The optical prescription in Tables 5A-5E describes an example embodimentof a folded telephoto lens system as illustrated in FIGS. 9A and 9B thatincludes four lens elements with refractive power and effective focallength f, and with refractive powers of the lens elements distributedsuch that the ratios of the focal lengths of the lens elements relativeto the system focal length f are |f1/f|=0.450, |f2/f|=0.791,|f3/f|=0.644, and |f4/f|=2.061. Lens element L1 is a biconvex lens withvertex radii of curvature R1/R2=−0.061, and L2 is negative meniscusshape and has vertex radii of curvature R3/R4=2.738. Lens element L3 hasvertex radii of curvature R5/R6=−0.051, and lens element L4 is biconvexand with vertex radii of curvature R7/R8=−0.451. The asphericcoefficients for the surfaces of the lens elements in lens system 510 inthe example embodiment are listed in Table 5C. Configuring lens system510 according to the arrangement of the power distribution of the lenselements, and adjusting the radii of curvature and aspheric coefficientas shown in Tables 5A-5E, the total track length (TTL), of the lenssystem 510 may be reduced (e.g., to 13.80 mm as shown in Table 5A) andaberration of the system may effectively be corrected to obtain opticalperformance of high image quality resolution, for an object scene atinfinity and for an object scene located <1000 mm distance, in a smallform factor camera 500.

FIGS. 11A and 11B are cross-sectional illustrations of another exampleembodiment of a compact telephoto camera 600 including a foldedtelephoto lens system 610. Lens system 610 includes four lens elements(601-604) with refractive power. Lens system 610 may be viewed as avariation of lens system 510 of FIGS. 9A and 9B since the light pathfolding optical element is a prism 640 and the elements of the twosystems 610 and 510 may be similar. However, in lens system 610, theaperture stop AS is located in the air space between the first lenselement L1 and second lens element L2. Moreover, in FIGS. 11A and 11B asin FIGS. 9A and 9B, the first lens group GR1 (including L1 and L2) andthe second lens group GR2 (including L3 and L4) may have lens elementsin close proximity that may be considered as air-spaced doublets.

Tables 6A-6E provide example values of various optical and physicalparameters of an example embodiment of a camera 600 and lens system 610as illustrated in FIGS. 11A and 11B. In at least some embodiments,system 610 may include a zooming mechanism for dynamically focusing anobject scene from infinity (object distance ≧20 meters) to near objectdistance, <1 meter. Tables 6A-6E may be referred to as providing anoptical prescription for a zoom lens system 610. In this exampleembodiment, lens system 610 may include a focusing lens group GR1including lens elements L1 and L2 that may be translated or actuated,together with the aperture stop along AX1, for focusing an object scenelocated at <1 meter. The zoom parameters for system 610 are listed inTable 6E. The zoom parameters shown in Table 6E for position 1 are theaxial thickness or space separation on surface #5 (along AX1) of lenselement L2 from the reflecting surface of prism 640 when the objectscene distance is at infinity (the optical prescription as listed inTable 6B). The corresponding optical prescription for an object scene at1 meter (position 2) is the same as the prescription listed in Table 6B,except that the object distance in surface #0 is replaced by 1000 mm,and the space separation of L2 on surface #5 is replaced by 0.9353 mm.As shown in Table 6E, the lens group GR1 moves by about 0.125 mm fromits nominal position 1 to position 2 for the lens system 610 to zoom andfocus object scene from >20 meters away from the camera to near objectscene at <1000 mm distance.

The optical prescription in Tables 6A-6E is for a zoom lens system 610with an effective focal length f of 14 mm at 555 nm wavelength, a focalratio of f/2.8, with 26 degrees FOV, TTL of 13.8 mm, and with TTL/fequal to 0.986. Lens system 610 is a compact folded imaging systemdesigned for visible spectrum covering 470 nm to 650 nm.

The lens elements L1, L2, L3, and L4 of lens system 610 may be composedof plastic materials with refractive indices and Abbe numbers as listedin Table 6B. In this example embodiment of lens system 610, the choiceof lens materials are the same as in the optical prescription for thelens system 110 as listed in Tables 1A-1D. Referring to the lens system610, the lens element L1 and L3 may be composed of a plastic materialhaving an Abbe number of V1=56.1. The lens elements L2 and L4 may becomposed of a plastic material with Abbe number V2=23.3.

Lens system 610 as specified in Tables 6A-6E is configured to correctoptical aberrations as described in reference to lens system 110 andTables 1A-1D. FIGS. 12A and 12B illustrate plots of the polychromaticray aberration curves over the half field of view (HFOV=13.0 degrees)for an object point on-axis (at 0 degrees) to an off-axis field point at13.0 degrees, and over the visible band ranging from 470 nm to 650 nmfor a compact folded telephoto lens system 610 as illustrated in FIGS.11A and 11B and described in Tables 6A-6E. Note that the plotsillustrated in FIGS. 12A and 12B show the well-corrected aberrations forboth focus positions 1 and 2 (i.e., the optical performance of lenssystem 610 for an object scene located at infinity, and for an objectscene located at <1000 mm distance).

The optical prescription in Tables 6A-6E describes an example embodimentof a folded telephoto lens system as illustrated in FIGS. 11A and 11Bthat includes four lens elements with refractive power and effectivefocal length f, and with refractive powers of the lens elementsdistributed such that the ratios of the focal lengths of the lenselements relative to the system focal length f are |f1/f|=0.446,|f2/f|=0.743, |f3/f|=0.714, and |f4/f|=2.097. Lens element L1 is abiconvex lens with vertex radii of curvature R1/R2=−0.008, and L2 isnegative meniscus shape and has vertex radii of curvature R3/R4=2.408.Lens element L3 has vertex radii of curvature R5/R6=−0.386, and lenselement L4 is biconvex with vertex radii of curvature R7/R8=−0.044. Theaspheric coefficients for the surfaces of the lens elements in lenssystem 610 in the example embodiment are listed in Table 6C. Configuringlens system 610 according to the arrangement of the power distributionof the lens elements, and adjusting the radii of curvature and asphericcoefficient as shown in Tables 6A-6E, the total track length (TTL), ofthe lens system 610 may be reduced (e.g., to 13.80 mm as shown in Table6A) and aberration of the system may effectively be corrected to obtainoptical performance of high image quality resolution, for an objectscene at infinity and for an object scene located <1000 mm distance, ina small form factor camera 600.

FIGS. 13A and 13B are cross-sectional illustrations of another exampleembodiment of a compact telephoto camera 700 including a foldedtelephoto lens system 710. Lens system 710 includes four lens elements(701-704) with refractive power. Lens system 710 may be viewed as avariation of lens system 610 of FIGS. 11A and 11B since the light pathfolding optical element is a prism 740 and the elements of the twosystems 710 and 610 may be similar. In lens system 710, as in system610, the aperture stop AS is located in the air space between the firstlens element L1 and second lens element L2. Moreover, in FIGS. 13A and13B as in FIGS. 11A and 11B, the first lens group GR1 (including L1 andL2) and the second lens group GR2 (including L3 and L4) may have lenselements in close proximity that may be considered as air-spaceddoublets. However, lens system 710, as illustrated in FIGS. 13A and 13B,may include a zooming mechanism for the photosensor 720 at the imageplane to dynamically focus an object scene from infinity (≧20 meters) tonear distance, e.g. less than a meter.

Tables 7A-7E provide example values of various optical and physicalparameters of an example embodiment of a camera 700 and lens system 710as illustrated in FIGS. 13A and 13B. In at least some embodiments,system 710 may include a zooming mechanism for dynamically focusing anobject scene from infinity (object distance ≧20 meters) to near objectdistance, <1 meter, by translating or actuating the photosensor 720 atthe image plane along the folded optical axis AX2. Tables 7A-7E may bereferred to as providing an optical prescription for a zoom lens system710. The zoom parameters for system 710 are listed in Table 7E. The zoomparameters shown in Table 7E for position 1 are the axial thickness orspace separation on surface #14 (along AX2) of the photosensor at theimage plane from the IR filter when the object scene distance is atinfinity (the optical prescription as listed in Table 7B). Thecorresponding optical prescription for an object scene at 1 meter(position 2) is the same as the prescription listed in Table 7B, exceptthat the object distance in surface #0 is replaced by 1000 mm, and thespace separation of photosensor at the image plane from the IR filter onsurface #14 is replaced by −1.1865 mm. As shown in Table 7E, thephotosensor at the image plane moves by about 0.194 mm from its nominalposition 1 to position 2 for the lens system 710 to zoom and focusobject scene from >20 meters away from the camera to near object sceneat <1000 mm distance.

The optical prescription in Tables 7A-7E is for a zoom lens system 710with an effective focal length f of 14 mm at 555 nm wavelength, a focalratio of f/2.8, with 26 degrees FOV, TTL of 13.8 mm, and with TTL/fequal to 0.986. Lens system 710 is a compact folded imaging systemdesigned for visible spectrum covering 470 nm to 650 nm.

The lens elements L1, L2, L3, and L4 of lens system 710 may be composedof plastic materials with refractive indices and Abbe numbers as listedin Table 7B. In this example embodiment of lens system 710, the choiceof lens materials are the same as in the optical prescription for thelens system 110 as listed in Tables 1A-1D. Referring to the lens system710, the lens element L1 and L3 may be composed of a plastic materialhaving an Abbe number of V1=56.1. The lens elements L2 and L4 may becomposed of a plastic material with Abbe number V2=23.3.

Lens system 710 as specified in Tables 7A-7E is configured to correctoptical aberrations as described in reference to lens system 110 andTables 1A-1D. FIGS. 14A and 14B illustrate plots of the polychromaticray aberration curves over the half field of view (HFOV=13.0 degrees)for an object point on-axis (at 0 degrees) to an off-axis field point at13.0 degrees, and over the visible band ranging from 470 nm to 650 nmfor a compact folded telephoto lens system 710 as illustrated in FIGS.13A and 13B and described in Tables 7A-7E. Note that the plotsillustrated in FIGS. 14A and 14B show the well-corrected aberrations forboth focus positions 1 and 2 (i.e., the optical performance of lenssystem 710 for an object scene located at infinity, and for an objectscene located at <1000 mm distance).

The optical prescription in Tables 7A-7E describes an example embodimentof a folded telephoto lens system as illustrated in FIGS. 13A and 13Bthat includes four lens elements with refractive power and effectivefocal length f, and with refractive powers of the lens elementsdistributed such that the ratios of the focal lengths of the lenselements relative to the system focal length f are |f1/f|=0.446,|f2/f|=0.745, |f3/f|=0.698, and |f4/f|=1.93. Lens element L1 is abiconvex lens with vertex radii of curvature R1/R2=−0.033, and L2 isnegative meniscus shape and has vertex radii of curvature R3/R4=2.604.Lens element L3 has vertex radii of curvature R5/R6=−0.755, and lenselement L4 has vertex radii of curvature R7/R8=0.058. The asphericcoefficients for the surfaces of the lens elements in lens system 710 inthe example embodiment are listed in Table 7C. Configuring lens system710 according to the arrangement of the power distribution of the lenselements, and adjusting the radii of curvature and aspheric coefficientas shown in Tables 7A-7E, the total track length (TTL), of the lenssystem 710 may be reduced (e.g., to 13.80 mm as shown in Table 7A) andaberration of the system may effectively be corrected to obtain opticalperformance of high image quality resolution, for an object scene atinfinity and for an object scene located <1000 mm distance, in a smallform factor camera 700.

FIG. 15A is a cross-sectional illustration of a compact camera 700Bincluding a variation 710B of the folded telephoto lens system 710 ofFIGS. 13A and 13B. Tables 8A-8E provide example values of variousoptical and physical parameters of folded telephoto lens system 710B asillustrated in FIG. 15A. In at least some embodiments, system 710B mayinclude a zooming mechanism for dynamically focusing an object scenefrom infinity (object distance ≧20 meters) to near object distance, <1meter, by translating or actuating the photosensor 720 at the imageplane along the folded optical axis AX2. Tables 8A-8E may be referred toas providing an optical prescription for an example variation 710B ofzoom lens system 710 of FIGS. 13A and 13B. The zoom parameters forsystem 710B are listed in Table 8E. The zoom parameters shown in Table8E for position 1 are the axial thickness or space separation on surface#14 (along AX2) of the photosensor at the image plane from the IR filterwhen the object scene distance is at infinity (the optical prescriptionas listed in Table 8B). The corresponding optical prescription for anobject scene at 1 meter (position 2) is the same as the prescriptionlisted in Table 8B, except that the object distance in surface #0 isreplaced by 1000 mm, and the space separation of photosensor at theimage plane from the IR filter on surface #14 is replaced by −1.0159 mm.As shown in Table 8E, the photosensor at the image plane moves by about0.194 mm from its nominal position 1 to position 2 for the lens system710B to zoom and focus object scene from >20 meters away from the camerato near object scene at <1000 mm distance.

The optical prescription in Tables 8A-8E is for a zoom lens system 710Bwith an effective focal length f of 14 mm at 555 nm wavelength, a focalratio of f/2.8, with 26 degrees FOV, TTL of 13.8 mm, and with TTL/fequal to 0.986. This lens system 710B is a compact folded imaging systemdesigned for visible spectrum covering 470 nm to 650 nm.

Lens system 710B as specified in Tables 8A-8E is configured to correctoptical aberrations as described in reference to lens system 110 andTables 1A-1D. FIGS. 15B and 15C illustrate plots of the polychromaticray aberration curves over the half field of view (HFOV=13.0 degrees)for an object point on-axis (at 0 degrees) to an off-axis field point at13.0 degrees, and over the visible band ranging from 470 nm to 650 nmfor a compact folded telephoto lens system 710B as illustrated in FIG.15A and described in Tables 8A-8E. Note that the plots illustrated inFIGS. 15B and 15C show the well-corrected aberrations for both focuspositions 1 and 2 (i.e., the optical performance of lens system 710B foran object scene located at infinity, and for an object scene located at<1000 mm distance).

The optical prescription in Tables 8A-8E describes an example embodimentof a folded telephoto lens system as illustrated in FIG. 15A thatincludes four lens elements with refractive power and effective focallength f, and with refractive powers of the lens elements distributedsuch that the ratios of the focal lengths of the lens elements relativeto the system focal length f are |f1/f|=0.442, |f2/f|=0.748,|f3/f|=0.697, and |f4/f|=2.138. Lens element L1 is a biconvex lenshaving an object side surface configured to be a conic surface withconic constant value of about k=−0.00518 and with vertex radii ofcurvature R1/R2=−0.050, and L2 is negative meniscus shape and has vertexradii of curvature R3/R4=2.583. Lens element L3 has vertex radii ofcurvature R5/R6=−0.573, and lens element L4 is biconvex and has vertexradii of curvature R7/R8=−0.502. The aspheric coefficients for thesurfaces of the lens elements in lens system 710B in the exampleembodiment are listed in Table 8C. Configuring lens system 710Baccording to the arrangement of the power distribution of the lenselements, and adjusting the radii of curvature and aspheric coefficientas shown in Tables 8A-8E, the total track length (TTL), of the lenssystem 710B may be reduced (e.g., to 13.80 mm as shown in Table 8A) andaberration of the system may effectively be corrected to obtain opticalperformance of high image quality resolution, for an object scene atinfinity and for an object scene located <1000 mm distance, in a smallform factor camera 700B.

FIG. 16A is a cross-sectional illustration of a compact camera 700Cincluding another variation 710C of the folded telephoto lens system 710of FIGS. 13A and 13B. Tables 9A-9E provide example values of variousoptical and physical parameters of folded telephoto lens system 710C asillustrated in FIG. 16A. In at least some embodiments, system 710C mayinclude a zooming mechanism for dynamically focusing an object scenefrom infinity (object distance ≧20 meters) to near object distance, <1meter, by translating or actuating the photosensor 720 at the imageplane along the folded optical axis AX2. Tables 9A-9E may be referred toas providing an optical prescription for an example variation 710C ofzoom lens system 710 of FIGS. 13A and 13B. The zoom parameters forsystem 710C are listed in Table 9E. The zoom parameters shown in Table9E for position 1 are the axial thickness or space separation on surface#14 (along AX2) of the photosensor at the image plane from the IR filterwhen the object scene distance is at infinity (the optical prescriptionas listed in Table 9B). The corresponding optical prescription for anobject scene at 1 meter (position 2) is the same as the prescriptionlisted in Table 9B, except that the object distance in surface #0 isreplaced by 1000 mm, and the space separation of photosensor at theimage plane from the IR filter on surface #14 is replaced by −1.0159 mm.As shown in Table 9E, the photosensor at the image plane moves by about0.194 mm from its nominal position 1 to position 2 for the lens system710C to zoom and focus object scene from >20 meters away from the camerato near object scene at <1000 mm distance.

The optical prescription in Tables 9A-9E is for a zoom lens system 710Cwith an effective focal length f of 14 mm at 555 nm wavelength, a focalratio of f/2.8, with 26 degrees FOV, TTL of 13.8 mm, and with TTL/fequal to 0.986. This lens system 710C is a compact folded imaging systemdesigned for visible spectrum covering 470 nm to 650 nm.

Lens system 710C as specified in Tables 9A-9E is configured to correctoptical aberrations as described in reference to lens system 110 andTables 1A-1D. FIGS. 16B and 16C illustrate plots of the polychromaticray aberration curves over the half field of view (HFOV=13.0 degrees)for an object point on-axis (at 0 degrees) to an off-axis field point at13.0 degrees, and over the visible band ranging from 470 nm to 650 nmfor a compact folded telephoto lens system 710C as illustrated in FIG.16A and described in Tables 9A-9E. Note that the plots illustrated inFIGS. 16B and 16C show the well-corrected aberrations for both focuspositions 1 and 2 (i.e., the optical performance of lens system 710C foran object scene located at infinity, and for an object scene located at<1000 mm distance).

The optical prescription in Tables 9A-9E describes an example embodimentof a folded telephoto lens system as illustrated in FIG. 16A thatincludes four lens elements with refractive power and effective focallength f, and with refractive powers of the lens elements distributedsuch that the ratios of the focal lengths of the lens elements relativeto the system focal length f are |f1/f|=0.437, |f2/f|=0.735,|f3/f|=0.672, and |f4/f|=1.930. Lens element L1 is a biconvex lenshaving an object side surface configured to be a spherical surface andwith vertex radii of curvature R1/R2=−0.134, and L2 is negative meniscusshape and has vertex radii of curvature R3/R4=3.300. Lens element L3 hasvertex radii of curvature R5/R6=−0.551, and lens element L4 is biconvexand has vertex radii of curvature R7/R8=−0.050. The asphericcoefficients for the surfaces of the lens elements in this third lenssystem 710C in the example embodiment are listed in Table 9C.Configuring this lens system 710C according to the arrangement of thepower distribution of the lens elements, and adjusting the radii ofcurvature and aspheric coefficient as shown in Tables 9A-9E, the totaltrack length (TTL), of the lens system 710C may be reduced (e.g., to13.80 mm as shown in Table 9A) and aberration of the system mayeffectively be corrected to obtain optical performance of high imagequality resolution, for an object scene at infinity and for an objectscene located <1000 mm distance, in a small form factor camera 700C.

FIGS. 17A and 17B are cross-sectional illustrations of another exampleembodiment of a compact telephoto camera 800 including a foldedtelephoto lens system 810. Lens system 810 includes four lens elements(801-804) with refractive power. Lens system 810 may be viewed as avariation of lens system 410 of FIGS. 7A and 7B since the light pathfolding optical element is a planar fold mirror 830 and the elements ofthe two systems 810 and 410 may be similar. In lens system 810, as insystem 410, the aperture stop AS is located in front and near the convexobject side surface of the first lens element L1. However, lens system810, as illustrated in FIGS. 17A and 17B, may include a zoomingmechanism for the photosensor 820 at the image plane to dynamicallyfocus an object scene from infinity (≧20 meters) to near distance, e.g.less than a meter. Moreover, as illustrated in FIGS. 17A and 17B, in atleast some embodiments the lenses in a second lens group GR2 (includingL3 (803) and L4 (804)) may be arranged to be not in close proximity witheach other, and L4 (lens 804) may have a concave image side surface.

Tables 10A-10E provide example values of various optical and physicalparameters of an example embodiment of a camera 800 and lens system 810as illustrated in FIGS. 17A and 17B. In at least some embodiments,system 810 may include a zooming mechanism for dynamically focusing anobject scene from infinity (object distance ≧20 meters) to near objectdistance, <1 meter, by translating or actuating the photosensor 820 atthe image plane along the folded optical axis AX2. Tables 10A-10E may bereferred to as providing an optical prescription for a zoom lens system810. The zoom parameters for system 810 are listed in Table 10E. Thezoom parameters shown in Table 10E for position 1 are the axialthickness or space separation on surface #16 (along AX2) of thephotosensor at the image plane from the IR filter when the object scenedistance is at infinity (the optical prescription as listed in Table10B). The corresponding optical prescription for an object scene at 1meter (position 2) is the same as the prescription listed in Table 10B,except that the object distance in surface #0 is replaced by 1000 mm,and the space separation of photosensor at the image plane from the IRfilter on surface #16 is replaced by −1.1938 mm. As shown in Table 10E,the photosensor 820 at the image plane moves by about 0.195 mm from itsnominal position 1 to position 2 for the lens system 810 to zoom andfocus object scene from >20 meters away from the camera to near objectscene at <1000 mm distance.

The optical prescription in Tables 10A-10E is for a zoom lens system 810with an effective focal length f of 14 mm at 555 nm wavelength, a focalratio of f/2.8, with 26 degrees FOV, TTL of 13.31 mm, and with TTL/fequal to 0.951. Lens system 810 is a compact folded imaging systemdesigned for visible spectrum covering 470 nm to 650 nm.

The lens elements L1, L2, L3, and L4 of lens system 810 may be composedof plastic materials with refractive indices and Abbe numbers as listedin Table 10B. In this example embodiment of lens system 810, the choiceof lens materials are the same as in the optical prescription for thelens system 110 as listed in Tables 1A-1D. Referring to the lens system810, the lens element L1 and L3 may be composed of a plastic materialhaving an Abbe number of V1=56.1. The lens elements L2 and L4 may becomposed of a plastic material with Abbe number V2=23.3.

Lens system 810 as specified in Tables 10A-10E is configured to correctoptical aberrations as described in reference to lens system 110 andTables 1A-1D. FIGS. 18A and 18B illustrate plots of the polychromaticray aberration curves over the half field of view (HFOV=13.0 degrees)for an object point on-axis (at 0 degrees) to an off-axis field point at13.0 degrees, and over the visible band ranging from 470 nm to 650 nmfor a compact folded telephoto lens system 810 as illustrated in FIGS.17A and 17B and described in Tables 10A-10E. Note that the plotsillustrated in FIGS. 18A and 18B show the well-corrected aberrations forboth focus positions 1 and 2 (i.e., the optical performance of lenssystem 810 for an object scene located at infinity, and for an objectscene located at <1000 mm distance).

The optical prescription in Tables 10A-10E describes an exampleembodiment of a folded telephoto lens system as illustrated in FIGS. 17Aand 17B that includes four lens elements with refractive power andeffective focal length f, and with refractive powers of the lenselements distributed such that the ratios of the focal lengths of thelens elements relative to the system focal length f are |f1/f|=0.491,|f2/f|=0.873, |f3/f|=1.033, and |f4/f|=3.095. Lens element L1 is abiconvex lens with vertex radii of curvature R1/R2=−0.155, and L2 isnegative meniscus shape and has vertex radii of curvature R3/R4=2.711.Lens element L3 has vertex radii of curvature R5/R6=−2.611, and lenselement L4 is a positive meniscus shape with a concave image sidesurface and has vertex radii of curvature R7/R8=0.923. The asphericcoefficients for the surfaces of the lens elements in lens system 810 inthe example embodiment are listed in Table 10C. Configuring lens system810 according to the arrangement of the power distribution of the lenselements, and adjusting the radii of curvature and aspheric coefficientas shown in Tables 10A-10E, the total track length (TTL), of the lenssystem 810 may be reduced (e.g., to 13.31 mm as shown in Table 10A) andaberration of the system may effectively be corrected to obtain opticalperformance of high image quality resolution, for an object scene atinfinity and for an object scene located <1000 mm distance, in a smallform factor camera 800.

FIGS. 19A and 19B are cross-sectional illustrations of another exampleembodiment of a compact telephoto camera 900 including a foldedtelephoto lens system 910. Lens system 910 includes four lens elements(901-904) with refractive power. Lens system 910 may be viewed as avariation of lens system 510 of FIGS. 9A and 9B since the light pathfolding optical element is a prism 940 and the elements of the twosystems 910 and 510 may be similar. In lens system 910, as in system510, the aperture stop AS is located in front and near the convex objectside surface of the first lens element L1. However, lens system 910, asillustrated in FIGS. 19A and 19B, may include a zooming mechanism forthe photosensor at the image plane to dynamically focus an object scenefrom infinity (≧20 meters) to near distance, e.g. less than a meter.Moreover, as illustrated in FIGS. 19A and 19B, in at least someembodiments, the lenses in a second lens group GR2 (including L3 (903)and L4 (904)) may be arranged along AX2 to be not in close proximitywith each other, and L4 (lens 904) may have a concave image sidesurface. In addition, in at least some embodiments, lens system 910 mayinclude a plano-convex lens element L1 (lens 901) with a convex objectside surface.

Tables 11A-11E provide example values of various optical and physicalparameters of an example embodiment of a camera 900 and lens system 910as illustrated in FIGS. 19A and 19B. In at least some embodiments,system 910 may include a zooming mechanism for dynamically focusing anobject scene from infinity (object distance ≧20 meters) to near objectdistance, <1 meter, by translating or actuating the photosensor 920 atthe image plane along the folded optical axis AX2. Tables 11A-11E may bereferred to as providing an optical prescription for a zoom lens system910. The zoom parameters for system 910 are listed in Table 11E. Thezoom parameters shown in Table 11E for position 1 are the axialthickness or space separation on surface #14 (along AX2) of thephotosensor 920 at the image plane from the IR filter when the objectscene distance is at infinity (the optical prescription as listed inTable 11B). The corresponding optical prescription for an object sceneat 1 meter (position 2) is the same as the prescription listed in Table11B, except that the object distance in surface #0 is replaced by 1000mm, and the space separation of photosensor 920 at the image plane fromthe IR filter on surface #14 is replaced by −1.4326 mm. As shown inTable 11E, the photosensor 920 at the image plane moves by about 0.195mm from its nominal position 1 to position 2 for the lens system 910 tozoom and focus object scene from >20 meters away from the camera to nearobject scene at <1000 mm distance.

The optical prescription in Tables 11A-11E is for a zoom lens system 910with an effective focal length f of 14 mm at 555 nm wavelength, a focalratio of f/2.8, with 26 degrees FOV, TTL of 13.80 mm, and with TTL/fequal to 0.986. Lens system 910 is a compact folded imaging systemdesigned for visible spectrum covering 470 nm to 650 nm.

The lens elements L1, L2, L3, and L4 of lens system 910 may be composedof plastic materials with refractive indices and Abbe numbers as listedin Table 11B. In this example embodiment of lens system 910, the choiceof lens materials are the same as in the optical prescription for thelens system 110 as listed in Tables 1A-1D. Referring to the lens system910, the lens element L1 and L3 may be composed of a plastic materialhaving an Abbe number of V1=56.1. The lens elements L2 and L4 may becomposed of a plastic material with Abbe number V2=23.3.

Lens system 910 as specified in Tables 11A-11E is configured to correctoptical aberrations as described in reference to lens system 110 andTables 1A-1D. FIGS. 20A and 20B illustrate plots of the polychromaticray aberration curves over the half field of view (HFOV=13.0 degrees)for an object point on-axis (at 0 degrees) to an off-axis field point at13.0 degrees, and over the visible band ranging from 470 nm to 650 nmfor a compact folded telephoto lens system 910 as illustrated in FIGS.19A and 19B and described in Tables 11A-11E. Note that the plotsillustrated in FIGS. 20A and 20B show the well-corrected aberrations forboth focus positions 1 and 2 (i.e., the optical performance of lenssystem 910 for an object scene located at infinity, and for an objectscene located at <1000 mm distance).

The optical prescription in Tables 11A-11E describes an exampleembodiment of a folded telephoto lens system as illustrated in FIGS. 19Aand 19B that includes four lens elements with refractive power andeffective focal length f, and with refractive powers of the lenselements distributed such that the ratios of the focal lengths of thelens elements relative to the system focal length f are |f1/f|=0.465,|f2/f|=0.834, |f3/f|=0.797, and |f4/f|=2.245. Lens element L1 is aplano-convex lens element having a convex object side surface with conicconstant value of about k=−0.02. Lens element L1 has vertex radii ofcurvature R1/R2=0. Lens element L2 is negative meniscus shape and hasvertex radii of curvature R3/R4=2.246. Lens element L3 has vertex radiiof curvature R5/R6=−2.251, and lens element L4 is a positive meniscusshape with a concave image side surface and has vertex radii ofcurvature R7/R8=0.806. The aspheric coefficients for the surfaces of thelens elements in lens system 910 in the example embodiment are listed inTable 11C. Configuring lens system 910 according to the arrangement ofthe power distribution of the lens elements, and adjusting the radii ofcurvature and aspheric coefficient as shown in Tables 11A-11E, the totaltrack length (TTL), of the lens system 910 may be reduced (e.g., to13.80 mm as shown in Table 11A) and aberration of the system mayeffectively be corrected to obtain optical performance of high imagequality resolution, for an object scene at infinity and for an objectscene located <1000 mm distance, in a small form factor camera 900.

FIGS. 21A and 21B are cross-sectional illustrations of another exampleembodiment of a compact telephoto camera 1000 including a foldedtelephoto lens system 1010. Lens system 1010 includes four lens elements(1001-1004) with refractive power. Lens system 1010 may be viewed as avariation of lens system 910 of FIGS. 19A and 19B since the light pathfolding optical element is a prism 1040 and the elements of the twosystems 1010 and 910 may be similar. In lens system 1010, the aperturestop AS is located in the space between the lens elements L1 and L2. Inthis example embodiment, the configuration of lens system 1010 maydiffer from that of lens system 910 only on the location of the aperturestop. Moreover, lens system 1010, as illustrated in FIGS. 21A and 21B,may also include a zooming mechanism for the photosensor 1020 at theimage plane to dynamically focus an object scene from infinity (≧20meters) to near distance, e.g. less than a meter. In at least someembodiments, lens system 1010 may include a plano-convex lens element L1(lens 1001) with a convex object side surface.

Tables 12A-12E provide example values of various optical and physicalparameters of an example embodiment of a camera 1000 and lens system1010 as illustrated in FIGS. 21A and 21B. In at least some embodiments,system 1010 may include a zooming mechanism for dynamically focusing anobject scene from infinity (object distance ≧20 meters) to near objectdistance, <1 meter, by translating or actuating the photosensor 1020 atthe image plane along the folded optical axis AX2. Tables 12A-12E may bereferred to as providing an optical prescription for a zoom lens system1010. The zoom parameters for system 1010 are listed in Table 12E. Thezoom parameters shown in Table 12E for position 1 are the axialthickness or space separation on surface #16 (along AX2) of thephotosensor 1020 at the image plane from the IR filter when the objectscene distance is at infinity (the optical prescription as listed inTable 12B). The corresponding optical prescription for an object sceneat 1 meter (position 2) is the same as the prescription listed in Table12B, except that the object distance in surface #0 is replaced by 1000mm, and the space separation of photosensor 1020 at the image plane fromthe IR filter on surface #16 is replaced by −1.4326 mm. As shown inTable 12E, the photosensor 1020 at the image plane moves by about 0.195mm from its nominal position 1 to position 2 for the lens system 1010 tozoom and focus object scene from >20 meters away from the camera to nearobject scene at <1000 mm distance. Note that while the parameters inoptical prescription for lens system 1010 are identical to thecorresponding parameters for lens system 910, the sequential numberingof the surfaces in the two prescriptions is different due to thedifference in the location of the aperture stop.

The optical prescription in Tables 12A-12E is for a zoom lens system1010 with an effective focal length f of 14 mm at 555 nm wavelength, afocal ratio of f/2.8, with 26 degrees FOV, TTL of 13.80 mm, and withTTL/f equal to 0.986. Lens system 1010 is a compact folded imagingsystem designed for visible spectrum covering 470 nm to 650 nm.

The lens elements L1, L2, L3, and L4 of lens system 1010 may be composedof plastic materials with refractive indices and Abbe numbers as listedin Table 12B. In this example embodiment of lens system 1010, the choiceof lens materials are the same as in the optical prescription for thelens system 910 as listed in Tables 11A-11E. Referring to the lenssystem 1010, the lens element L1 and L3 may be composed of a plasticmaterial having an Abbe number of V1=56.1. The lens elements L2 and L4may be composed of a plastic material with Abbe number V2=23.3.

Lens system 1010 as specified in Tables 12A-12E is configured to correctoptical aberrations as described in reference to lens system 910 andTables 11A-11E. FIGS. 22A and 22B illustrate plots of the polychromaticray aberration curves over the half field of view (HFOV=13.0 degrees)for an object point on-axis (at 0 degrees) to an off-axis field point at13.0 degrees, and over the visible band ranging from 470 nm to 650 nmfor a compact folded telephoto lens system 1010 as illustrated in FIGS.21A and 21B and described in Tables 12A-12E. Note that the plotsillustrated in FIGS. 22A and 22B show the well-corrected aberrations forboth focus positions 1 and 2 (i.e., the optical performance of lenssystem 1010 for an object scene located at infinity, and for an objectscene located at <1000 mm distance).

The optical prescription in Tables 12A-12E describes an exampleembodiment of a folded telephoto lens system as illustrated in FIGS. 21Aand 21B that includes four lens elements with refractive power andeffective focal length f, and with refractive powers of the lenselements distributed such that the ratios of the focal lengths of thelens elements relative to the system focal length f are |f1/f|=0.465,|f2/f|=0.834, |f3/f|=0.797, and |f4/f|=2.245. Lens element L1 is aplano-convex lens element having a convex object side surface with conicconstant value of about k=−0.02. Lens element L1 has vertex radii ofcurvature R1/R2=0. Lens element L2 is negative meniscus shape and hasvertex radii of curvature R3/R4=2.246. Lens element L3 has vertex radiiof curvature R5/R6=−2.251, and lens element L4 is a positive meniscusshape with a concave image side surface and has vertex radii ofcurvature R7/R8=0.806. The aspheric coefficients for the surfaces of thelens elements in lens system 1010 in the example embodiment are listedin Table 12C. Configuring lens system 1010 according to the arrangementof the power distribution of the lens elements, and adjusting the radiiof curvature and aspheric coefficient as shown in Tables 12A-12E, thetotal track length (TTL), of the lens system 1010 may be reduced (e.g.,to 13.80 mm as shown in Table 12A) and aberration of the system mayeffectively be corrected to obtain optical performance of high imagequality resolution, for an object scene at infinity and for an objectscene located <1000 mm distance, in a small form factor camera 1000.

FIG. 23 is a high-level flowchart of a method for capturing images usinga camera with a folded telephoto lens system as illustrated in FIGS. 1Athrough 22B, according to at least some embodiments. As indicated at1100, light from an object field in front of the camera is received at afirst lens element of the camera. In some embodiments, an aperture stopmay be located at the front vertex of the lens system, or between thefront vertex and the object plane. Alternatively, the aperture stop maybe located behind the front vertex of the lens system, for example atthe first lens element, or between the first and second lens elements.As indicated at 1102, the first lens element refracts the light to asecond lens element. As indicated at 1104, the light is then refractedby the second lens element to a light path folding element with areflecting surface (e.g., a prism or plane mirror). As indicated at1106, the light path folding element changes the direction of the lightto direct the light to a third lens element. As indicated at 1108, thelight is then refracted by the third lens element to a fourth lenselement. As indicated at 1110, the light is refracted by the fourth lenselement to form an image at an image plane at or near the surface of aphotosensor. As indicated at 1112, the image may be captured by thephotosensor. While not shown, in some embodiments, the light may passthrough an infrared filter that may for example be located between thefourth lens element and the photosensor.

Summarizing, the incoming light from the object field passes through therefracting optical surfaces of the optical elements located on a firstoptical axis, AX1 (e.g., the first and second lens elements). Areflecting surface of the light path folding element changes thedirection of the incoming light from the first optical axis AX1 to asecond optical axis, AX2, and the incoming light on the second opticalaxis passes through the refracting elements (the third and fourth lenselements) to the image plane at or near the photosensor on the secondoptical axis.

In some embodiments, the optical elements may be configured asillustrated in FIGS. 1A and 1B and according to the optical prescriptionprovided in Tables 1A-1D. Alternatively, the optical elements may beconfigured as illustrated in FIGS. 3A and 3B and according to theoptical prescription provided in Tables 2A-2E. As yet anotheralternative, the optical elements may be configured as illustrated inFIGS. 5A and 5B and according to the optical prescription provided inTables 3A-3E. As yet another alternative, the optical elements may beconfigured as illustrated in FIGS. 7A and 7B and according to theoptical prescription provided in Tables 4A-4E. As yet anotheralternative, the optical elements may be configured as illustrated inFIGS. 9A and 9B and according to the optical prescription provided inTables 5A-5E. As yet another alternative, the optical elements may beconfigured as illustrated in FIGS. 11A and 11B and according to theoptical prescription provided in Tables 6A-6E. As yet anotheralternative, the optical elements may be configured as illustrated inFIGS. 13A and 13B and according to the optical prescription provided inTables 7A-7E. As yet another alternative, the optical elements may beconfigured as illustrated in FIG. 15A and according to the opticalprescription provided in Tables 8A-8E. As yet another alternative, theoptical elements may be configured as illustrated in FIG. 16A andaccording to the optical prescription provided in Tables 9A-9E. As yetanother alternative, the optical elements may be configured asillustrated in FIGS. 17A and 17B and according to the opticalprescription provided in Tables 10A-10E. As yet another alternative, theoptical elements may be configured as illustrated in FIGS. 19A and 19Band according to the optical prescription provided in Tables 11A-11E. Asyet another alternative, the optical elements may be configured asillustrated in FIGS. 21A and 21B and according to the opticalprescription provided in Tables 12A-12E. However, note that variationson the examples given in the Figures and Tables are possible whileachieving similar optical results.

Example Lens System Tables

The following Tables provide example values for various optical andphysical parameters of example embodiments of the folded telephoto lenssystems and cameras as described herein in reference to FIGS. 1A through21B. Tables 1A-1D correspond to an example embodiment of lens system 110with four lens elements and fold mirror as illustrated in FIGS. 1A-1B.Tables 2A-2E provide example values of various optical and physicalparameters of an example embodiment of a camera 200 and lens system 210as illustrated in FIGS. 3A and 3B. Tables 3A-3E provide example valuesof various optical and physical parameters of an example embodiment of acamera 300 and lens system 310 as illustrated in FIGS. 5A and 5B. Tables4A-4E provide example values of various optical and physical parametersof an example embodiment of a camera 400 and lens system 410 asillustrated in FIGS. 7A and 7B. Tables 5A-5E provide example values ofvarious optical and physical parameters of an example embodiment of acamera 500 and lens system 510 as illustrated in FIGS. 9A and 9B. Tables6A-6E provide example values of various optical and physical parametersof an example embodiment of a camera 600 and lens system 610 asillustrated in FIGS. 11A and 11B. Tables 7A-7E provide example values ofvarious optical and physical parameters of an example embodiment of acamera 700 and lens system 710 as illustrated in FIGS. 13A and 13B.Tables 8A-8E provide example values of various optical and physicalparameters of folded telephoto lens system 710B as illustrated in FIG.15A. Tables 9A-9E provide example values of various optical and physicalparameters of folded telephoto lens system 710C as illustrated in FIG.16A. Tables 10A-10E provide example values of various optical andphysical parameters of an example embodiment of a camera 800 and lenssystem 810 as illustrated in FIGS. 17A and 17B. Tables 11A-11E provideexample values of various optical and physical parameters of an exampleembodiment of a camera 900 and lens system 910 as illustrated in FIGS.19A and 19B. Tables 12A-12E provide example values of various opticaland physical parameters of an example embodiment of a camera 1000 andlens system 1010 as illustrated in FIGS. 21A and 21B.

In the Tables, all dimensions are in millimeters (mm) unless otherwisespecified. “S#” stands for surface number. A positive radius indicatesthat the center of curvature is to the right of the surface. A negativeradius indicates that the center of curvature is to the left of thesurface. “INF” stands for infinity (as used in optics). “ASP” indicatesan aspheric surface, and “FLT” indicates a flat surface. The thickness(or separation) is the axial distance to the next surface. The designwavelengths represent wavelengths in the spectral band of the imagingoptical system.

In the Tables, note the following sign convention on the opticalparameters (e.g., radii of curvature and axial thickness or separation,focal lengths) when the direction of the light path change afterreflecting from the mirror surface or prism surface. Following areflecting surface element, a positive radius indicates that the centerof curvature is to the left of the surface, a negative radius indicatesthat the center of curvature is to the right of the surface, and thethickness or axial separation has negative sign. This sign convention iswell known to those skilled in the art of optical design. In the Tablesthe absolute value of the system focal length f is listed.

For the materials of the lens elements and IR filter, a refractive indexN_(d) at the helium d-line wavelength is provided, as well as an Abbenumber V_(d) relative to the d-line and the C- and F-lines of hydrogen.The Abbe number, V_(d), may be defined by the equation:

V _(d)=(N _(d)−1)/(N _(F) −N _(C)),

where N_(F) and N_(C) are the refractive index values of the material atthe F and C lines of hydrogen, respectively.

Referring to the Tables of aspheric constants (Tables 1C, 2C, 3C, 4C,5C, 6C, 7C, 8C, 9C, 10C, 11C, and 12C), the aspheric equation describingan aspherical surface may be given by:

$Z = {\frac{{cr}^{2}}{1 + \sqrt{1 - {\left( {1 + K} \right)c^{2}r^{2}}}} + {Ar}^{4} + {Br}^{6} + {Cr}^{8} + {Dr}^{10} + {Er}^{12} + {Fr}^{14} + {Gr}^{16} + {Hr}^{18} + \ldots}$

where Z is the sag of the surface parallel to the Z-axis (for allembodiments the Z-axis coincide with the optical axis), c is thecurvature of the surface (the reciprocal of the radius of curvature ofthe surface), K is the conic constant, and A, B, C, D, E, F, G, and Hare the aspheric coefficients. In the Tables “E” denotes exponentialnotation (powers of 10).

In Tables (1D-12D), the decentering constants of the reflecting surfacein the fold mirror or prism element are listed for the exampleembodiments. As shown in Tables 1D-12D, the reflecting surface of thefold mirror or prism is oriented 45 degrees relative to the optical axisof L1 and L2 and thus the folded optical axis of L3 and L4 is configuredto be 90 degrees relative to the optical axis of L1 and L2. However, theangular orientation of the reflecting surface of the fold mirror orprism element may be configured to a desired value to suit a desiredlight path direction and lens system packaging requirements.

Note that the values given in the following Tables for the variousparameters in the various embodiments of the folded telephoto lenssystem are given by way of example and are not intended to be limiting.For example, one or more of the parameters for one or more of thesurfaces of one or more of the lens elements in the example embodiments,as well as parameters for the materials of which the elements arecomposed, may be given different values while still providing similarperformance for the lens system. In particular, note that some of thevalues in the Tables may be scaled up or down for larger or smallerimplementations of a camera using an embodiment of a folded telephotolens system as described herein.

Further note that the surface numbers (S#) of the elements in thevarious embodiments of the folded telephoto lens system as shown in theTables are listed from the first surface 0 at the object plane to thelast surface at the image plane. Since number and location of elementmay vary in embodiments, the surface number(s) that correspond to someelements may vary in the different Tables. For example, in the firstsets of Tables (e.g., Tables 1B, 6B, 7B, 8B, 9B, 11B,), the aperturestop is surface 3, and the first lens element (L1) has surfaces 1 and 2.However, in Tables 2B, 3B, 4B, 5B, 10B, and 12B, the location of theaperture stop is different, and thus the surface numbers are differentin the Tables. For example, in Tables 2B, 3B, 4B, 5B, 10B, and 12B, theaperture stop is surface 2, and the first lens element (L1) has surfaces4 and 5. In particular, note that where reference is given to the radiusof curvature (R#) of the surfaces of the lens element (L#) in thisdocument, the reference (R#) used (e.g., R1 and R2 for the surfaces oflens element L1) are the same for all of the embodiments, and may but donot necessarily correspond to the surface numbers of the lens elementsas given in the Tables.

In some embodiments the folded telephoto lens system is a zoom systemequipped and configured with a moving lens group or element forfocusing. Further note that the zoom parameters of the exampleembodiments are denoted by an asterisk (*) in Tables 2B-12B and alsolisted in the Tables for zoom parameters (i.e., Tables 2E-12E). The zoomparameters are the axial separation or space separation that changeswhen the lens system is zoomed to focus from an object scene at infinity(object distance >20 meters) to a nearby object scene located at <1meter from the camera. In some embodiments (e.g., Tables 2B, 3B, 4B, 5B,and 6B) the focusing lens group, (GR1), includes the lens elements L1and L2 and the aperture stop. The axial position of GR1 when the foldedtelephoto lens system is focused at infinity is denoted by position 1and the corresponding axial position of GR1 when the lens system isfocused at nearby object scene is denoted by position 2. Exampleembodiments of a folded telephoto lens system in which the lens systemmay include a rail and mechanism to translate or actuate the axialposition of GR1 for focusing are illustrated in FIGS. 3A, 5A, 7A, 9A,and 11A, and the corresponding zoom parameters are shown in Tables 2E,3E, 4E, 5E, and 6E. For example in the embodiment as illustrated in FIG.5A, GR1 may be displaced or translated from its axial position 1 (i.e.,its focus position for an object scene at infinity) by about 0.215 mm toposition 2 (as shown in Table 3E) for the telephoto system to focus anearby object scene located 500 mm from the camera. In another exampleembodiment as illustrated in FIG. 9A, GR1 may be displaced or translatedfrom its axial position 1 (i.e., its focus position for an object sceneat infinity) by about 0.12 mm to position 2 (as shown in Table 5E) forthe telephoto system to focus a nearby object located 500 mm from thecamera.

Note that the choice of GR1 as a movable or focusing group for thevarious embodiments of the folded telephoto lens systems in Tables 2B-E,3B-E, 4B-E, 5B-E, and 6B-E are given by way of example and are notintended to be limiting. For example, a focusing group, GR2, includingthe lens elements L3 and L4 in the folded axis may be used while stillproviding similar performance for the folded telephoto lens system.Moreover, the object distance or focus displacement range of thefocusing lens group may be scaled up or down for larger or smallerimplementations of a camera using an embodiment of a folded telephotolens system as described herein.

In some embodiments the folded telephoto lens system is a zoom system inwhich the photosensor may be moved or translated for focusing an objectscene from infinity (object distance ≧20 meters) to a near distance,e.g. less than a meter. Example embodiments of folded telephoto lenssystems in which the photosensor is the focusing element are illustratedin FIGS. 13A, 17A, 19A, and 21A, with corresponding optical designprescriptions given in Tables 7A-7E, 8A-8E, 9A-9E, 10A-10E, 11A-11E, and12A-12E. Further note that the zoom parameters of the exampleembodiments are denoted by an asterisk (*) in these Tables. The zoomparameters are the axial separation or space separation of thephotosensor at the image plane that changes when the lens system iszoomed to focus from an object scene at infinity (object distance ≧20meters, denoted by zoom position 1) to a nearby object scene located at<1 meter (denoted by zoom position 2) from the camera. For example inthe embodiment as illustrated in FIG. 13A, a particular example of atelephoto lens system with optical axis folded using a prism with lensdesign prescription given in Table 9A-9E, the photosensor at the imageplane may be displaced or translated or actuated from its axial position1 (i.e., its focus position for an object scene at infinity) by about0.194 mm to position 2 (as shown by the zoom parameters in Table 9E) forthe telephoto system to focus a nearby object scene located 1 meter awayfrom the camera. In another example embodiment as illustrated in FIG.17A, a particular example of a telephoto lens system with optical axisfolded using a plane mirror with lens design prescription given inTables 10A-10E, the photosensor at the image plane may be displaced ortranslated or actuated from its axial position 1 by about 0.195 mm toposition 2 (as shown by the zoom parameters in Table 10E) for thetelephoto system to focus a nearby object located 1 meter distance fromthe camera.

TABLE 1A Focal length (f) 10.0 mm F-Number 2.8 Half FOV 12° Total tracklength TTL 8.8 Telephoto ratio (TTL/f) 0.880 Design wavelengths 650 nm,610 nm, 555 nm, 510 nm, 470 nm

TABLE 1B Thickness Refractive Abbe Surface Radius Or Index NumberElement (S#) R Shape Separation Material N_(d) V_(d) Object plane 0 INFFLT INF L1 1 2.489 ASP 1.1892 Plastic 1.544 56.1 2 −33.023 ASP 0.1023Aperture Stop 3 INF FLT 0.1286 L2 4 6.517 ASP 0.4155 Plastic 1.632 23.35 2.275 ASP 2.1916 Decenter (1) Mirror 6 INF FLT −2.1916 Refl Bend (1)L3 7 −28.082 ASP −0.5675 Plastic 1.544 56.1 8 −2.339 ASP −0.1236 L4 9−6.571 ASP −0.7883 Plastic 1.632 23.3 10  11.711 ASP −0.2073 IR filter11  INF FLT −0.3000 Glass 1.516 64.1 12  INF FLT −0.5852 Image plane 13 INF FLT

TABLE 1C ASPHERIC CONSTANTS Curvature A B C D S# (c) K E F G H 10.40170668 0.47210442 −1.19980E−03 −4.55996E−03 2.22996E−03 −7.51167E−047.45241E−05 0.00000E+00 0.00000E+00 0.00000E+00 2 −0.03028212 0.000000008.85341E−03 −3.00683E−03 2.03529E−04 3.78264E−04 −1.52828E−042.93711E−05 0.00000E+00 0.00000E+00 4 0.15343691 −2.47026832−6.02965E−03 3.72173E−03 −5.06520E−03 2.81896E−03 −4.62047E−040.00000E+00 0.00000E+00 0.00000E+00 5 0.43958924 −5.00998338 4.66655E−02−1.23712E−02 1.13551E−02 −8.65658E−03 5.07613E−03 −1.05505E−030.00000E+00 0.00000E+00 7 −0.03561002 0.00000000 7.58585E−02−8.42664E−03 −2.48418E−03 6.75744E−04 1.02719E−04 −3.89598E−050.00000E+00 0.00000E+00 8 −0.42753025 0.00000000 8.62773E−02−1.20125E−02 3.12257E−04 4.60730E−04 −6.26149E−05 0.00000E+000.00000E+00 0.00000E+00 9 −0.15219201 0.00000000 9.93244E−03−3.33689E−03 1.53672E−04 1.37639E−04 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 10 0.08539012 0.00000000 2.25546E−02 −1.19528E−021.78162E−03 2.54279E−05 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00

TABLE 1D DECENTERING CONSTANTS Alpha Gamma Decenter X Y Z (degrees) Beta(degrees) (degrees) D(1) and 0.000 0.000 0.000 45.000 0.000 0.000 Bend(1)

TABLE 2A Focal length (f) 14.0 mm F-Number  2.8 Half FOV 9.5° Totaltrack length TTL 13.6 Telephoto ratio (TTL/f)  0.971 Design wavelengths650 nm, 610 nm, 555 nm, 510 nm, 470 nm

TABLE 2B Thickness Refractive Abbe Surface Or Index Number Element (S#)Radius R Shape Separation Material N_(d) V_(d) Object plane 0 INF FLTINF *1 1 INF FLT  0.7500 Aperture Stop 2 INF FLT −0.7500 3 INF FLT 0.0000 L1 4 4.482 ASP  1.2406 Plastic 1.544 56.1 5 −30.806 ASP  0.1000L2 6 −9.962 ASP  0.3000 Plastic 1.632 23.3 7 387.112 ASP  0.4594 *2 8INF  2.500 Decenter (1) Fold Mirror 9 INF FLT −2.500 Refl Bend (1) 10 INF FLT −1.2921 L3 11  −4.391 ASP −0.4600 Plastic 1.544 56.1 12  −2.870ASP −1.8939 L4 13  −4.509 ASP −1.0328 Plastic 1.632 23.3 14  −4.336 ASP−0.6616 IR filter 15  INF FLT −0.3000 Glass 1.516 64.1 16  INF FLT−0.8596 Image plane 17  INF FLT

TABLE 2C ASPHERIC CONSTANTS Curvature A B c D S# (c) K E F G H 40.22313714 −1.20747815 2.18925E−03 −4.15897E−04 1.57623E−04 −2.25930E−051.25335E−06 0.00000E+00 0.00000E+00 0.00000E+00 5 −0.03246104 0.00000000−7.43087E−05 8.40447E−04 −3.24246E−05 −4.07050E−05 7.10947E−06−3.45484E−07 0.00000E+00 0.00000E+00 6 −0.10038639 0.000000001.69399E−02 −1.79418E−03 7.82291E−05 5.06342E−07 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 7 0.258323E−02 0.00000000 1.88597E−02−2.90690E−03 3.47662E−04 −1.97174E−05 3.39851E−07 0.00000E+000.00000E+00 0.00000E+00 11 −0.22774223 0.00000000 1.01087E−021.11881E−03 −7.70792E−05 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 12 −0.34846896 0.00000000 1.39314E−02 1.23303E−03−3.71598E−05 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+0013 −0.22177011 0.00000000 1.27671E−02 −1.14186E−04 3.59233E−050.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 14−0.23061022 0.00000000 1.85383E−02 −1.75209E−04 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00

TABLE 2D DECENTERING CONSTANTS Alpha Gamma Decenter X Y Z (degrees) Beta(degrees) (degrees) D (1) and 0.000 0.000 0.000 45.000 0.000 0.000 Bend(1)

TABLE 2E ZOOM PARAMETERS *Zoom Parameters Position - 1 Position - 2 *1INF 500.0000 mm *2 0.4594 mm  0.7756 mm

TABLE 3A Focal length (f) 14.0 mm F-Number  2.8 Half FOV 9.5° Totaltrack length TTL 14.0 Telephoto ratio (TTL/f)  1.0 Design wavelengths650 nm, 610 nm, 555 nm, 510 nm, 470 nm

TABLE 3B Thickness Refractive Abbe Surface Radius Or Index NumberElement (S#) R Shape Separation Material N_(d) V_(d) Object plane 0 INFFLT INF *1 1 INF FLT  0.7500 Aperture Stop 2 INF FLT −0.7500 3 INF FLT 0.0000 L1 4 4.338 ASP  1.2309 Plastic 1.544 56.1 5 −18.372 ASP  0.1001L2 6 −7.831 ASP  0.3003 Plastic 1.632 23.3 7 −41.341 ASP  0.3687 *2 8INF  2.500 Glass 1.516 64.1 Decenter (1) Prism 9 INF FLT −2.500 ReflBend (1) 10 INF FLT −2.2538 L3 11 −24.767 ASP −0.3000 Plastic 1.544 56.112 −4.726 ASP −2.3748 L4 13 −3.280 ASP −0.4299 Plastic 1.632 23.3 14−3.249 ASP −0.6499 IR filter 15 INF FLT −0.3000 Glass 1.516 64.1 16 INFFLT −0.6913 Image plane 17 INF FLT

TABLE 3C ASPHERIC CONSTANTS Curvature A B C D S# (c) K E F G H 40.23052084 −1.14413857 2.25289E−03 −4.35985E−04 1.58126E−04 −2.19956E−051.26707E−06 0.00000E+00 0.00000E+00 0.00000E+00 5 −0.05443033 0.00000000−1.44949E−04 8.53033E−04 −2.98583E−05 −4.00958E−05 6.97172E−06−3.43148E−07 0.00000E+00 0.00000E+00 6 −0.12769868 0.000000001.69726E−02 −1.80031E−03 7.69661E−05 2.47266E−07 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 7 −0.02418909 −7.00000000 1.84888E−02−2.91139E−03 3.37520E−04 −2.07874E−05 6.34032E−07 0.00000E+000.00000E+00 0.00000E+00 11 −0.04037587 0.00000000 1.90995E−023.44071E−04 −1.04565E−04 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 12 −0.21161332 0.00000000 1.63295E−02 4.10809E−05−1.16671E−04 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+0013 −0.30488896 0.00000000 9.69672E−03 5.27266E−05 5.46157E−060.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 14−0.30780162 0.00000000 1.39980E−02 1.30106E−04 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00

TABLE 3D DECENTERING CONSTANTS Alpha Gamma Decenter X Y Z (degrees) Beta(degrees) (degrees) D (1) and 0.000 0.000 0.000 45.000 0.000 0.000 Bend(1)

TABLE 3E ZOOM PARAMETERS *Zoom Parameters Position - 1 Position - 2 *1INF 500.0000 mm *2 0.3687 mm  0.5841 mm

TABLE 4A Focal length (f) 14.0 mm F-Number  2.8 Half FOV 13.0° Totaltrack length TTL 13.65 Telephoto ratio (TTL/f)  0.975 Design wavelengths650 nm, 610 nm, 555 nm, 510 nm, 470 nm

TABLE 4B Thickness Refractive Abbe Surface Radius Or Index NumberElement (S#) R Shape Separation Material N_(d) V_(d) Object plane 0 INFFLT INF *1 1 INF FLT  0.9500 Aperture Stop 2 INF FLT −0.9500 3 INF FLT 0.0000 L1 4 3.546 ASP  1.2116 Plastic 1.544 56.1 5 34.706 ASP  0.1000L2 6 4.185 ASP  0.3304 Plastic 1.632 23.3 7 2.570 ASP  1.058 *2 8 INF 2.600 Decenter (1) Fold Mirror 9 INF FLT −2.600 Refl Bend (1) 10 INFFLT −1.1685 L3 11 −6.125 ASP −0.8000 Plastic 1.544 56.1 12 −3.838 ASP−0.605 L4 13 −6.139 ASP −1.2406 Plastic 1.632 23.3 14 −7.239 ASP −0.2353IR filter 15 INF FLT −0.3000 Glass 1.516 64.1 16 INF FLT −1.4007 Imageplane 17 INF FLT

TABLE 4C ASPHERIC CONSTANTS Curvature A B C D S# (c) K E F G H 40.28198896 0.54385086 −8.97071E−04 −9.60216E−04 2.36450E−04 −3.98644E−051.86235E−06 0.00000E+00 0.00000E+00 0.00000E+00 5 0.02881363 0.000000001.91639E−03 −4.30535E−04 2.98399E−05 1.79192E−05 −5.17362E−064.63950E−07 0.00000E+00 0.00000E+00 6 0.23892744 0.00000000 −4.17807E−031.73786E−04 8.87137E−06 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 7 0.38917309 0.00000000 −5.31055E−03 −9.65246E−045.62061E−04 −1.21186E−04 8.07452E−06 0.00000E+00 0.00000E+00 0.00000E+0011 −0.16325655 0.00000000 3.50794E−03 3.67081E−04 −3.26907E−051.51614E−07 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 12−0.26056890 0.00000000 4.52217E−03 3.96480E−04 −1.67156E−05 0.00000E+000.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 13 −0.162886520.00000000 5.45284E−03 −2.82832E−04 3.06431E−05 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 0.00000E+00 14 −0.13813978 0.000000007.80530E−03 −2.50679E−04 1.58616E−05 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00

TABLE 4D DECENTERING CONSTANTS Alpha Gamma Decenter X Y Z (degrees) Beta(degrees) (degrees) D (1) and 0.000 0.000 0.000 45.000 0.000 0.000 Bend(1)

TABLE 4E ZOOM PARAMETERS *Zoom Parameters Position - 1 Position - 2 *1INF 1000.0000 mm *2 1.0580 mm   1.2608 mm

TABLE 5A Focal length (f) 14.0 mm F-Number  2.8 Half FOV 13.0° Totaltrack length TTL 13.8 Telephoto ratio (TTL/f)  0.986 Design wavelengths650 nm, 610 nm, 555 nm, 510 nm, 470 nm

TABLE 5B Thickness Refractive Abbe Surface Radius Or Index NumberElement (S#) R Shape Separation Material N_(d) V_(d) Object plane 0 INFFLT INF *1 1 INF FLT  0.7500 Aperture Stop 2 INF FLT −0.7500 3 INF FLT 0.0000 L1 4 3.618 ASP  1.4878 Plastic 1.544 56.1 5 −59.628 ASP  0.1219L2 6 11.979 ASP  0.4773 Plastic 1.632 23.3 7 4.374 ASP  0.8130 *2 8 INF 2.400 Glass 1.516 64.1 Decenter (1) Prism 9 INF FLT −2.400 Refl Bend(1) 10 INF FLT −2.1507 L3 11 5.178 ASP −0.4773 Plastic 1.544 56.1 12−101.937 ASP −0.1496 L4 13 −26.534 ASP −1.2293 Plastic 1.632 23.3 1458.901 ASP −0.9645 IR filter 15 INF FLT −0.3000 Glass 1.516 64.1 16 INFFLT −0.8287 Image plane 17 INF FLT

TABLE 5C ASPHERIC CONSTANTS Curvature A B C D S# (c) K E F G H 40.27640302 0.00000000 −5.63077E−05 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 5 −0.01677063 0.000000001.93942E−03 −6.28480E−05 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 6 0.08347616 0.00000000 1.49766E−03 1.64055E−04−1.58262E−05 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+007 0.22862733 0.00000000 2.65386E−03 8.18076E−04 −9.40594E−05 2.29745E−050.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 11 0.19312010 0.000000006.76209E−03 1.89354E−04 −3.63715E−05 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 12 −0.980997E−02 0.00000000 6.07998E−035.81915E−04 −6.05979E−05 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 13 −0.03768697 0.00000000 6.93739E−03 3.61496E−040.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+0014 0.01697772 0.00000000 6.85996E−03 −1.64325E−04 1.49222E−050.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00

TABLE 5D DECENTERING CONSTANTS Alpha Gamma Decenter X Y Z (degrees) Beta(degrees) (degrees) D (1) and 0.000 0.000 0.000 45.000 0.000 0.000 Bend(1)

TABLE 5E ZOOM PARAMETERS *Zoom Parameters Position - 1 Position - 2 *1INF 1000.0000 mm *2 0.8130 mm   0.9337 mm

TABLE 6A Focal length (f) 14.0 mm F-Number 2.8 Half FOV 13.0° Totaltrack length TTL 13.80 Telephoto ratio (TTL/f) 0.986 Design wavelengths650 nm, 610 nm, 555 nm, 510 nm, 470 nm

TABLE 6B Thickness Refractive Abbe Surface Radius Or Index NumberElement (S#) R Shape Separation Material N_(d) V_(d) Object plane 0 INFFLT INF *1 L1 1 3.432 ASP  1.4878 Plastic 1.544 56.1 2 −427.795 ASP 0.1249 Aperture Stop 3 INF FLT  0.0000 L2 4 9.016 ASP  0.4773 Plastic1.632 23.3 5 3.744 ASP  0.8101 *2 Prism 6 INF FLT  2.4000 Glass 1.51664.1 Decenter (1) 7 INF FLT −2.4000 Refl Bend (1) 8 INF FLT −1.8069 L3 97.617 ASP −0.4773 Plastic 1.544 56.1 10 −19.736 ASP −0.2735 L4 11−19.527 ASP −1.2163 Plastic 1.632 23.3 12 442.388 ASP −1.0074 IR filter13 INF FLT −0.3000 Glass 1.516 64.1 14 INF FLT −1.0185 Image plane 15INF FLT

TABLE 6C ASPHERIC CONSTANTS Curvature A B C D S# (c) K E F G H 10.29138806 0.00000000 −1.44067E−04 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 2 −0.233757E−020.00000000 1.89869E−03 −7.02580E−05 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 0.00000E+00 4 0.11090854 0.00000000 1.59436E−031.21991E−04 −1.96237E−05 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 5 0.26712423 0.00000000 3.13985E−03 1.08838E−03 −1.76427E−044.61768E−05 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 9 0.131283070.00000000 8.00460E−03 7.61401E−05 −6.72293E−05 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 0.00000E+00 10 −0.05066791 0.000000005.50266E−03 6.81569E−04 −8.35284E−05 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 11 −0.05121242 0.00000000 4.86978E−035.07665E−04 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 12 0.226046E−02 0.00000000 6.31481E−03 −1.61244E−041.96753E−05 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00

TABLE 6D DECENTERING CONSTANTS Alpha Gamma Decenter X Y Z (degrees) Beta(degrees) (degrees) D (1) and 0.000 0.000 0.000 45.000 0.000 0.000 Bend(1)

TABLE 6E ZOOM PARAMETERS *Zoom Parameters Position - 1 Position - 2 *1INF 1000.0000 mm *2 0.8101 mm   0.9353 mm

TABLE 7A Focal length (f) 14.0 mm F-Number 2.8 Half FOV 13.0° Totaltrack length TTL 13.80 Telephoto ratio (TTL/f) 0.986 Design wavelengths650 nm, 610 nm, 555 nm, 510 nm, 470 nm

TABLE 7B Thickness Refractive Abbe Surface Radius Or Index NumberElement (S#) R Shape Separation Material N_(d) V_(d) Object plane 0 INFFLT INF *1 L1 1 3.499 ASP  1.4878 Plastic 1.544 56.1 2 −107.676 ASP 0.1781 Aperture Stop 3 INF FLT  0.0000 L2 4 10.358 ASP  0.4773 Plastic1.632 23.3 5 3.977 ASP  0.7568 Prism 6 INF FLT  2.4000 Glass 1.516 64.1Decenter (1) 7 INF FLT −2.4000 Refl Bend (1) 8 INF FLT −1.6868 L3 99.441 ASP −0.4773 Plastic 1.544 56.1 10 −12.500 ASP −0.4665 L4 11−16.258 ASP −1.1784 Plastic 1.632 23.3 12 −279.920 ASP −0.9981 IR filter13 INF FLT −0.3000 Glass 1.516 64.1 14 INF FLT −0.9929 *2 Image plane 15INF FLT

TABLE 7C ASPHERIC CONSTANTS Curvature A B C D S# (c) K E F G H 10.28583608 0.00000000 −1.19539E−05 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 2 −0.928709E−020.00000000 1.95937E−03 −7.07338E−05 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 0.00000E+00 4 0.09654674 0.00000000 9.13450E−042.40771E−04 −2.37733E−05 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 5 0.25144903 0.00000000 2.39937E−03 9.75313E−04 −1.00714E−043.16440E−05 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 9 0.105921310.00000000 1.26288E−02 6.63474E−05 −7.62897E−05 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 0.00000E+00 10 −0.07999826 0.000000008.98375E−03 6.82970E−04 −8.21604E−05 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 11 −0.06150852 0.00000000 3.11410E−037.80267E−04 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 12 −0.357245E−02 0.00000000 5.27002E−03 3.43482E−051.19644E−05 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00

TABLE 7D DECENTERING CONSTANTS Alpha Gamma Decenter X Y Z (degrees) Beta(degrees) (degrees) D (1) and 0.000 0.000 0.000 45.000 0.000 0.000 Bend(1)

TABLE 7E ZOOM PARAMETERS *Zoom Parameters Position - 1 Position - 2 *1INF 1000.0000 mm *2 −0.9929 mm  −1.1865 mm

TABLE 8A Focal length (f) 14.0 mm F-Number 2.8 Half FOV 13.0° Totaltrack length TTL 13.80 Telephoto ratio (TTL/f) 0.986 Design wavelengths650 nm, 610 nm, 555 nm, 510 nm, 470 nm

TABLE 8B Thickness Refractive Abbe Surface Radius Or Index NumberElement (S#) R Shape Separation Material N_(d) V_(d) Object plane 0 INFFLT INF *1 L1 1 3.522 ASP   1.4878 Plastic 1.544 56.1 2 −71.013 ASP  0.1940 Aperture Stop 3 INF FLT   0.0000 L2 4 10.256 ASP   0.4773Plastic 1.632 23.3 5 3.971 ASP   0.7409 Prism 6 INF FLT   2.4000 Glass1.516 64.1 Decenter(1) 7 INF FLT −2.4000 Ref1 Bend (1) 8 INF FLT −1.5751L3 9 8.434 ASP −0.4773 Plastic 1.544 56.1 10 −14.716 ASP −0.4940 L4 11−28.490 ASP −1.4485 Plastic 1.632 23.3 12 56.728 ASP −0.9833 IR filter13 INF FLT −0.3000 Glass 1.516 64.1 14 INF FLT −0.8218 *2 Image plane 15INF FLT

TABLE 8C ASPHERIC CONSTANTS Curvature A B C D S# (c) K E F G H 10.28395906 −0.517598E−02 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 2 −0.01408199 0.000000001.81178E−03 −5.54784E−05 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 4 0.09749985 0.00000000 −2.69337E−05 3.33931E−04−2.58978E−05 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+005 0.25181927 0.00000000 1.36407E−03 9.87870E−04 −8.43651E−05 2.77159E−050.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 9 0.11856531 0.000000001.33108E−02 −1.79246E−05 −3.95551E−05 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 0.00000E+00 10 −0.06795318 0.000000009.73642E−03 5.65860E−04 −4.72380E−05 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 11 −0.03509973 0.00000000 2.69371E−038.57758E−04 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 12 0.01762783 0.00000000 4.46700E−03 1.34739E−04 0.00000E+000.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00

TABLE 8D DECENTERING CONSTANTS Alpha Gamma Decenter X Y Z (degrees) Beta(degrees) (degrees) D(1) and 0.000 0.000 0.000 45.000 0.000 0.000 Bend(1)

TABLE 8E ZOOM PARAMETERS *Zoom Parameters Position - 1 Position - 2 *1INF 1000.0000 mm *2 −0.8218 mm  −1.0159 mm

TABLE 9A Focal length (f) 14.0 mm F-Number 2.8 Half FOV 13.0° Totaltrack length TTL 13.80 Telephoto ratio (TTL/f) 0.986 Design wavelengths650 nm, 610 nm, 555 nm, 510 nm, 470 nm

TABLE 9B Thickness Refractive Abbe Surface Radius Or Index NumberElement (S#) R Shape Separation Material N_(d) V_(d) Object plane 0 INFFLT INF *1 L1 1 3.721 SPH   1.4878 Plastic 1.544 56.1 2 −27.760 ASP  0.3032 Aperture Stop 3 INF FLT   0.0000 L2 4 14.817 ASP   0.4773Plastic 1.632 23.3 5 4.489 ASP   0.6317 Prism 6 INF FLT   2.4000 Glass1.516 64.1 Decenter(1) 7 INF FLT −2.4000 Ref1 Bend (1) 8 INF FLT −1.3966L3 9 8.022 ASP −0.4773 Plastic 1.544 56.1 10 −14.550 ASP −0.5606 L4 11−18.050 ASP −1.3308 Plastic 1.632 23.3 12 368.617 ASP −1.0966 IR filter13 INF FLT −0.3000 Glass 1.516 64.1 14 INF FLT −0.9381 *2 Image plane 15INF FLT

TABLE 9C ASPHERIC CONSTANTS Curvature A B C D S# (c) K E F G H 2−0.03602272 0.00000000 1.91094E−03 −5.17947E−05 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 4 0.06748787 0.00000000−1.65783E−03 5.49257E−04 −3.70457E−05 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 0.00000E+00 5 0.22275500 0.00000000 −1.04395E−037.46179E−04 3.78305E−05 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 9 0.12466179 0.00000000 1.55699E−02 6.84117E−05 0.00000E+000.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 10−0.06872911 0.00000000 1.21357E−02 4.42811E−04 −3.81887E−05 0.00000E+000.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 11 −0.055402710.00000000 4.16689E−03 7.89754E−04 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 0.00000E+00 12 0.271284E−02 0.000000005.29754E−03 1.38400E−04 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00

TABLE 9D DECENTERING CONSTANTS Alpha Gamma Decenter X Y Z (degrees) Beta(degrees) (degrees) D(1) and 0.000 0.000 0.000 45.000 0.000 0.000 Bend(1)

TABLE 9E ZOOM PARAMETERS *Zoom Parameters Position - 1 Position - 2 *1INF 1000.0000 mm *2 −0.8218 mm  −1.0159 mm

TABLE 10A Focal length (f) 14.0 mm F-Number 2.8 Half FOV 13.0° Totaltrack length TTL 13.31 Telephoto ratio (TTL/f) 0.951 Design wavelengths650 nm, 610 nm, 555 nm, 510 nm, 470 nm

TABLE 10B Thickness Refractive Abbe Surface Radius Or Index NumberElement (S#) R Shape Separation Material N_(d) V_(d) Object plane 0 INFFLT INF *1 1 INF FLT   0.6900 Aperture Stop 2 INF FLT −0.6900 3 INF FLT  0.0000 L1 4 4.277 ASP   1.2058 Plastic 1.544 56.1 5 −27.570 ASP  0.2000 L2 6 13.055 ASP   0.4500 Plastic 1.632 23.3 7 4.815 ASP  0.6684 8 INF   2.600 Decenter (1) Fold Mirror 9 INF FLT −2.600 Ref1Bend (1) 10 INF FLT −0.7500 L3 11 28.651 ASP −0.5500 Plastic 1.544 56.112 −10.973 ASP −0.8447 L4 13 −4.812 ASP −1.3000 Plastic 1.632 23.3 14−5.215 ASP −0.8403 IR filter 15 INF FLT −0.3000 Glass 1.516 64.1 16 INFFLT −0.9992 *2 Image plane 17 INF FLT

TABLE 10C ASPHERIC CONSTANTS Curvature A B C D S# (c) K E F G H 40.23380693 1.17051019 −8.65800E−04 −6.87900E−04 1.88217E−04 −3.48494E−052.00098E−06 0.00000E+00 0.00000E+00 0.00000E+00 5 −0.03627133 0.000000002.95689E−03 −2.62826E−04 −1.54736E−05 1.50074E−05 −3.12495E−062.81509E−07 0.00000E+00 0.00000E+00 6 0.07659706 0.00000000 −2.95054E−032.89846E−04 −6.59856E−06 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 7 0.20768752 0.00000000 −3.78752E−03 −3.68603E−044.42156E−04 −9.03606E−05 6.61024E−06 0.00000E+00 0.00000E+00 0.00000E+0011 0.03490279 0.00000000 1.25192E−02 4.22790E−04 4.19747E−05 0.00000E+000.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 12 −0.091130980.00000000 1.05552E−02 3.05385E−04 −2.00649E−05 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 0.00000E+00 13 −0.20779716 0.000000003.96238E−03 −1.35200E−04 3.91503E−06 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 14 −0.19177105 0.00000000 5.72695E−03−3.44193E−04 8.76331E−06 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00

TABLE 10D DECENTERING CONSTANTS Alpha Gamma Decenter X Y Z (degrees)Beta (degrees) (degrees) D(1) and 0.000 0.000 0.000 45.000 0.000 0.000Bend (1)

TABLE 10E ZOOM PARAMETERS *Zoom Parameters Position - 1 Position - 2 *1INF 1000.0000 mm *2 −0.9992 mm  −1.1938 mm

TABLE 11A Focal length (f) 14.0 mm F-Number 2.8 Half FOV 13.0° Totaltrack length TTL 13.80 Telephoto ratio (TTL/f) 0.986 Design wavelengths650 nm, 610 nm, 555 nm, 510 nm, 470 nm

TABLE 11B Thickness Refractive Abbe Surface Radius Or Index NumberElement (S#) R Shape Separation Material N_(d) V_(d) Object plane 0 INFFLT INF *1 L1 1 3.556 ASP   1.4952 Plastic 1.544 56.1 2 INF FLT   0.1209Aperture Stop 3 INF FLT   0.0000 L2 4 8.933 ASP   0.4773 Plastic 1.63223.3 5 3.977 ASP   0.8067 Prism 6 INF FLT   2.4000 Glass 1.516 64.1Decenter(1) 7 INF FLT −2.4000 Ref1 Bend (1) 8 INF FLT −1.0007 L3 919.925 ASP −0.4773 Plastic 1.544 56.1 10 −8.852 ASP −1.2389 L4 11 −4.679ASP −0.5946 Plastic 1.632 23.3 12 −5.802 ASP −1.2507 IR filter 13 INFFLT −0.3000 Glass 1.516 64.1 14 INF FLT −1.2378 *2 Image plane 15 INFFLT

TABLE 11C ASPHERIC CONSTANTS Curvature A B C D S# (c) K E F G H 10.28123926 −0.01993120 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 4 0.11193957 0.00000000−2.27240E−03 8.19742E−05 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 5 0.25145987 0.00000000 −4.85039E−05 5.29461E−04−7.64021E−05 2.05357E−05 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+009 0.05018867 0.00000000 1.43044E−02 5.94240E−04 6.49751E−05 0.00000E+000.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 10 −0.112969630.00000000 1.15308E−02 4.31319E−04 −2.96326E−05 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 0.00000E+00 11 −0.21373168 0.000000005.26380E−03 −8.40412E−05 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 12 −0.17236676 0.00000000 6.58069E−03−2.54870E−04 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00

TABLE 11D DECENTERING CONSTANTS Alpha Gamma Decenter X Y Z (degrees)Beta (degrees) (degrees) D(1) and 0.000 0.000 0.000 45.000 0.000 0.000Bend (1)

TABLE 11E ZOOM PARAMETERS *Zoom Parameters Position - 1 Position - 2 *1INF 1000.0000 mm *2 −1.2378 mm  −1.4326 mm

TABLE 12A Focal length (f) 14.0 mm F-Number 2.8 Half FOV 13.0° Totaltrack length TTL 13.8 Telephoto ratio (TTL/f) 0.986 Design wavelengths650 nm, 610 nm, 555 nm, 510 nm, 470 nm

TABLE 12B Thickness Refractive Abbe Surface Radius Or Index NumberElement (S#) R Shape Separation Material N_(d) V_(d) Object plane 0 INFFLT INF *1 1 INF FLT   0.7500 Aperture Stop 2 INF FLT −0.7500 3 INF FLT  0.0000 L1 4 3.556 ASP   1.4952 Plastic 1.544 56.1 5 INF FLT   0.1209L2 6 8.933 ASP   0.4773 Plastic 1.632 23.3 7 3.977 ASP   0.8067 8 INF  2.400 Glass 1.516 64.1 Decenter (1) Prism 9 INF FLT −2.400 Ref1 Bend(1) 10 INF FLT −1.0007 L3 11 19.925 ASP −0.4773 Plastic 1.544 56.1 12−8.852 ASP −1.2389 L4 13 −4.679 ASP −0.5946 Plastic 1.632 23.3 14 −5.802ASP −1.2507 IR filter 15 INF FLT −0.3000 Glass 1.516 64.1 16 INF FLT−1.2378 *2 Image plane 17 INF FLT

TABLE 12C ASPHERIC CONSTANTS Curvature A B C D S# (c) K E F G H 40.28123926 −0.01993120 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 6 0.11193957 0.00000000−2.27240E−03 8.19742E−05 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 7 0.25145987 0.00000000 −4.85039E−05 5.29461E−04−7.64021E−05 2.05357E−05 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+0011 0.05018867 0.00000000 1.43044E−02 5.94240E−04 6.49751E−05 0.00000E+000.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 12 −0.112969630.00000000 1.15308E−02 4.31319E−04 −2.96326E−05 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 0.00000E+00 13 −0.21373168 0.000000005.26380E−03 −8.40412E−05 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00 0.00000E+00 14 −0.17236676 0.00000000 6.58069E−03−2.54870E−04 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+00 0.00000E+000.00000E+00

TABLE 12D DECENTERING CONSTANTS Alpha Gamma Decenter X Y Z (degrees)Beta (degrees) (degrees) D(1) and 0.000 0.000 0.000 45.000 0.000 0.000Bend (1)

TABLE 12E ZOOM PARAMETERS *Zoom Parameters Position - 1 Position - 2 *1INF 1000.0000 mm *2 −1.2378 mm  −1.4326 mm

Example Computing Device

FIG. 24 illustrates an example computing device, referred to as computersystem 2000, that may include or host embodiments of the camera asillustrated in FIGS. 1A through 23. In addition, computer system 2000may implement methods for controlling operations of the camera and/orfor performing image processing of images captured with the camera. Indifferent embodiments, computer system 2000 may be any of various typesof devices, including, but not limited to, a personal computer system,desktop computer, laptop, notebook, tablet or pad device, slate, ornetbook computer, mainframe computer system, handheld computer,workstation, network computer, a camera, a set top box, a mobile device,a wireless phone, a smartphone, a consumer device, video game console,handheld video game device, application server, storage device, atelevision, a video recording device, a peripheral device such as aswitch, modem, router, or in general any type of computing or electronicdevice.

In the illustrated embodiment, computer system 2000 includes one or moreprocessors 2010 coupled to a system memory 2020 via an input/output(I/O) interface 2030. Computer system 2000 further includes a networkinterface 2040 coupled to I/O interface 2030, and one or moreinput/output devices 2050, such as cursor control device 2060, keyboard2070, and display(s) 2080. Computer system 2000 may also include one ormore cameras 2090, for example one or more telephoto cameras asdescribed above with respect to FIGS. 1A through 23, which may also becoupled to I/O interface 2030, or one or more telephoto cameras asdescribed above with respect to FIGS. 1A through 23 along with one ormore other cameras such as wide-field cameras.

In various embodiments, computer system 2000 may be a uniprocessorsystem including one processor 2010, or a multiprocessor systemincluding several processors 2010 (e.g., two, four, eight, or anothersuitable number). Processors 2010 may be any suitable processor capableof executing instructions. For example, in various embodimentsprocessors 2010 may be general-purpose or embedded processorsimplementing any of a variety of instruction set architectures (ISAs),such as the x86, PowerPC, SPARC, or MIPS ISAs, or any other suitableISA. In multiprocessor systems, each of processors 2010 may commonly,but not necessarily, implement the same ISA.

System memory 2020 may be configured to store program instructions 2022and/or data 2032 accessible by processor 2010. In various embodiments,system memory 2020 may be implemented using any suitable memorytechnology, such as static random access memory (SRAM), synchronousdynamic RAM (SDRAM), nonvolatile/Flash-type memory, or any other type ofmemory. In the illustrated embodiment, program instructions 2022 may beconfigured to implement various interfaces, methods and/or data forcontrolling operations of camera 2090 and for capturing and processingimages with integrated camera 2090 or other methods or data, for exampleinterfaces and methods for capturing, displaying, processing, andstoring images captured with camera 2090. In some embodiments, programinstructions and/or data may be received, sent or stored upon differenttypes of computer-accessible media or on similar media separate fromsystem memory 2020 or computer system 2000.

In one embodiment, I/O interface 2030 may be configured to coordinateI/O traffic between processor 2010, system memory 2020, and anyperipheral devices in the device, including network interface 2040 orother peripheral interfaces, such as input/output devices 2050. In someembodiments, I/O interface 2030 may perform any necessary protocol,timing or other data transformations to convert data signals from onecomponent (e.g., system memory 2020) into a format suitable for use byanother component (e.g., processor 2010). In some embodiments, I/Ointerface 2030 may include support for devices attached through varioustypes of peripheral buses, such as a variant of the Peripheral ComponentInterconnect (PCI) bus standard or the Universal Serial Bus (USB)standard, for example. In some embodiments, the function of I/Ointerface 2030 may be split into two or more separate components, suchas a north bridge and a south bridge, for example. Also, in someembodiments some or all of the functionality of I/O interface 2030, suchas an interface to system memory 2020, may be incorporated directly intoprocessor 2010.

Network interface 2040 may be configured to allow data to be exchangedbetween computer system 2000 and other devices attached to a network2085 (e.g., carrier or agent devices) or between nodes of computersystem 2000. Network 2085 may in various embodiments include one or morenetworks including but not limited to Local Area Networks (LANs) (e.g.,an Ethernet or corporate network), Wide Area Networks (WANs) (e.g., theInternet), wireless data networks, some other electronic data network,or some combination thereof. In various embodiments, network interface2040 may support communication via wired or wireless general datanetworks, such as any suitable type of Ethernet network, for example;via telecommunications/telephony networks such as analog voice networksor digital fiber communications networks; via storage area networks suchas Fibre Channel SANs, or via any other suitable type of network and/orprotocol.

Input/output devices 2050 may, in some embodiments, include one or moredisplay terminals, keyboards, keypads, touchpads, scanning devices,voice or optical recognition devices, or any other devices suitable forentering or accessing data by computer system 2000. Multipleinput/output devices 2050 may be present in computer system 2000 or maybe distributed on various nodes of computer system 2000. In someembodiments, similar input/output devices may be separate from computersystem 2000 and may interact with one or more nodes of computer system2000 through a wired or wireless connection, such as over networkinterface 2040.

As shown in FIG. 24, memory 2020 may include program instructions 2022,which may be processor-executable to implement any element or action tosupport integrated camera 2090, including but not limited to imageprocessing software and interface software for controlling camera 2090.In at least some embodiments, images captured by camera 2090 may bestored to memory 2020. In addition, metadata for images captured bycamera 2090 may be stored to memory 2020.

Those skilled in the art will appreciate that computer system 2000 ismerely illustrative and is not intended to limit the scope ofembodiments. In particular, the computer system and devices may includeany combination of hardware or software that can perform the indicatedfunctions, including computers, network devices, Internet appliances,PDAs, wireless phones, pagers, video or still cameras, etc. Computersystem 2000 may also be connected to other devices that are notillustrated, or instead may operate as a stand-alone system. Inaddition, the functionality provided by the illustrated components mayin some embodiments be combined in fewer components or distributed inadditional components. Similarly, in some embodiments, the functionalityof some of the illustrated components may not be provided and/or otheradditional functionality may be available.

Those skilled in the art will also appreciate that, while various itemsare illustrated as being stored in memory or on storage while beingused, these items or portions of them may be transferred between memoryand other storage devices for purposes of memory management and dataintegrity. Alternatively, in other embodiments some or all of thesoftware components may execute in memory on another device andcommunicate with the illustrated computer system 2000 via inter-computercommunication. Some or all of the system components or data structuresmay also be stored (e.g., as instructions or structured data) on acomputer-accessible medium or a portable article to be read by anappropriate drive, various examples of which are described above. Insome embodiments, instructions stored on a computer-accessible mediumseparate from computer system 2000 may be transmitted to computer system2000 via transmission media or signals such as electrical,electromagnetic, or digital signals, conveyed via a communication mediumsuch as a network and/or a wireless link. Various embodiments mayfurther include receiving, sending or storing instructions and/or dataimplemented in accordance with the foregoing description upon acomputer-accessible medium. Generally speaking, a computer-accessiblemedium may include a non-transitory, computer-readable storage medium ormemory medium such as magnetic or optical media, e.g., disk orDVD/CD-ROM, volatile or non-volatile media such as RAM (e.g. SDRAM, DDR,RDRAM, SRAM, etc.), ROM, etc. In some embodiments, a computer-accessiblemedium may include transmission media or signals such as electrical,electromagnetic, or digital signals, conveyed via a communication mediumsuch as network and/or a wireless link.

The methods described herein may be implemented in software, hardware,or a combination thereof, in different embodiments. In addition, theorder of the blocks of the methods may be changed, and various elementsmay be added, reordered, combined, omitted, modified, etc. Variousmodifications and changes may be made as would be obvious to a personskilled in the art having the benefit of this disclosure. The variousembodiments described herein are meant to be illustrative and notlimiting. Many variations, modifications, additions, and improvementsare possible. Accordingly, plural instances may be provided forcomponents described herein as a single instance. Boundaries betweenvarious components, operations and data stores are somewhat arbitrary,and particular operations are illustrated in the context of specificillustrative configurations. Other allocations of functionality areenvisioned and may fall within the scope of claims that follow. Finally,structures and functionality presented as discrete components in theexample configurations may be implemented as a combined structure orcomponent. These and other variations, modifications, additions, andimprovements may fall within the scope of embodiments as defined in theclaims that follow.

What is claimed is:
 1. A camera, comprising: a photosensor configured tocapture light projected onto a surface of the photosensor; and a foldedtelephoto lens system comprising a plurality of optical elementsarranged along a first optical axis and a second optical axis of thecamera and configured to: refract light from an object field located infront of the camera along the first optical axis; redirect the light onto the second optical axis; and refract the light on the second opticalaxis to form an image of a scene at an image plane at or near thesurface of the photosensor.
 2. The camera as recited in claim 1,wherein, to redirect the light on to the second optical axis, the lenssystem includes a light path folding element configured to reflect thelight from the first optical axis on to the second optical axis.
 3. Thecamera as recited in claim 1, wherein the plurality of optical elementsincludes a plurality of refractive lenses, wherein at least one surfaceof at least one of the plurality of refractive lenses is aspheric. 4.The camera as recited in claim 1, wherein at least one of the pluralityof optical elements is composed of a first plastic material, and whereinat least one other of the plurality of optical elements is composed of asecond plastic material with different optical characteristics than thefirst plastic material.
 5. The camera as recited in claim 1, wherein atleast one of the plurality of optical elements is configured totranslate or move along a respective optical axis to adjust focus of theimage of the scene at the photosensor.
 6. The camera as recited in claim1, wherein the photosensor is configured to translate or move along arespective optical axis to adjust focus of the image of the scene at thephotosensor.
 7. The camera as recited in claim 1, wherein the lenssystem has effective focal length f, wherein total track length (TTL) ofthe lens system is 14 millimeters or less, and wherein telephoto ratio(TTL/f) of the lens system is within a range of 0.8 to 1.0.
 8. Thecamera as recited in claim 1, wherein effective focal length f of thelens system is within a range of 8 millimeters to 14 millimeters, andwherein focal ratio of the lens system is within a range of 2.4 to 10.9. The camera as recited in claim 1, wherein effective focal length f ofthe lens system is 14 millimeters, and wherein focal ratio of the lenssystem is 2.8.
 10. The camera as recited in claim 1, wherein theplurality of optical elements includes, in order along the first andsecond optical axes from an object side of the camera to an image sideof the camera: one or more lens elements on the first optical axis; alight path folding element configured to redirect the light from thefirst optical axis on to the second optical axis; and one or more lenselements on the second optical axis.
 11. The camera as recited in claim10, wherein the first optical axis includes a first lens element and asecond lens element, wherein the telephoto lens system further includesan aperture stop located at or in front of the first lens element,between the first lens element and the second lens element, or betweenthe second lens element and a reflecting surface of the light pathfolding element.
 12. The camera as recited in claim 11, wherein theaperture stop is adjustable to provide a focal ratio within a range of2.4 to
 10. 13. The camera as recited in claim 1, wherein the pluralityof optical elements includes, in order along the first and secondoptical axes from an object side of the camera to an image side of thecamera: a first lens element with positive refractive power having aconvex object side surface; a second lens element with negativerefractive power; a third lens element with negative refractive power;and a fourth lens element with positive refractive power.
 14. The cameraas recited in claim 13, wherein the lens system has effective focallength f, wherein the first lens element is a biconvex lens, and whereinfocal length f1 of the first lens element satisfies the condition:0.4<|f1/f|<0.8.
 15. The camera as recited in claim 13, wherein the lenssystem has effective focal length f, and wherein the first lens elementhas vertex radii of curvature R1 and R2 and satisfies the condition:0≦|R1/R2|<6.1.
 16. The camera as recited in claim 13, wherein the lenssystem has effective focal length f, and wherein the second lens elementhas negative focal length f2, vertex radii of curvature R3 and R4, andsatisfies the conditions:(0.5<|f2/f|<3.3) and (|R3/R4|<3.3).
 17. The camera as recited in claim13, wherein the plurality of optical elements further includes a lightpath folding element located between the second lens element and thethird lens element that reflects the light from the first optical axison to the second optical axis, wherein the light path folding element isone of a mirror or a prism.
 18. A folded telephoto lens system,comprising: a plurality of refractive lens elements arranged along afolded optical axis of the telephoto lens system, wherein at least onesurface of at least one of the plurality of lens elements is aspheric;wherein the telephoto lens system has effective focal length f within arange of 10.0 millimeters to 14 millimeters, wherein total track length(TTL) of the telephoto lens system is 14 millimeters or less, andwherein the telephoto ratio (TTL/f) of the lens system is within a rangeof 0.8 to 1.0; and wherein at least one of the plurality of lenselements is composed of a first material, and wherein at least one otherof the plurality of lens elements is composed of a second material withdifferent optical characteristics than the first material.
 19. Thefolded telephoto lens system as recited in claim 18, wherein theplurality of lens elements includes, in order along the folded opticalaxis from an object side of the telephoto lens system to an image sideof the telephoto lens system: a first lens element with positiverefractive power having a convex object side surface; a second lenselement with negative refractive power; a light path folding elementconfigured to redirect light from a first optical path of the foldedoptical axis on to a second optical path of the folded optical axis; athird lens element with negative refractive power; and a fourth lenselement with positive refractive power.
 20. The folded telephoto lenssystem as recited in claim 19, wherein the second lens element isnegative meniscus shape and has a concave image side surface.
 21. Thefolded telephoto lens system as recited in claim 19, wherein the fourthlens element is positive meniscus shape and has a concave image sidesurface.
 22. The folded telephoto lens system as recited in claim 19,wherein the fourth lens element is a biconvex lens.
 23. A device,comprising: one or more processors; one or more cameras; and a memorycomprising program instructions executable by at least one of the one ormore processors to control operations of the one or more cameras;wherein at least one of the one or more cameras is a small form factortelephoto camera comprising: a photosensor configured to capture lightprojected onto a surface of the photosensor; and a folded telephoto lenssystem configured to: refract light from an object field located infront of the camera along a first optical axis; redirect the light on toa second optical axis; and refract the light on the second optical axisto form an image of a scene at an image plane at or near the surface ofthe photosensor; and wherein the folded telephoto lens system haseffective focal length f, wherein the total track length (TTL) of thelens system is 14.0 millimeters or less, and wherein telephoto ratio(TTL/f) of the lens system is within a range of 0.8 to 1.0.